White public attention has been focused almost exclusively on South Korean businessman Tongsun Park in th federal investigations of foreign influence-buying in Congress, there have been indications all along that the South Korean effort was more than a one-man show.

Investigators have been told that Korean diplomats as well as other "unofficial" agents were involved - indeed, that Park was viewed as a lobbying rival by the South Korean ambassador.

Thus even if the South Korean government were to put Park on the next plane back to Washington to face a 36-count felony indictment, the Justice Department and congressional investigators would not be able to wrap up their inquiries with a full picture of the Korean campaign.

The full story may never known, because the Korean government, not surprisingly, has been unwilling to cooperate with previous requests by U.S. authorities to question other important witnesses and get access to financial records.

For instance, embassy officials have threatened to go to court to block the House Committee on Standards of Official Conduct from obtaining complete bank records of some diplomats suspected of making cash payments to members of Congress. Likewise, they have declined to make former diplomats available for questioning.

There is evidence already on the public record that indicates why federal investigators are so interested in testimony of others besides Tongsun Park. For example:

A former Korean diplomat has testified that during the early 1970s he once witnessed Kim Dong Jo, then the ambassador to the United States, stuffing envelopes full of $100 bills for delivery to Capitol Hill.

The diplomat, Jai Hyon Lee, who sought United States asylum in 1973, aslo recalled that the embassy used to received regular shipments of American currency from Seoul in the diplomatic pouch.

Tongsun Park - who federal investigators believe often exaggerated the number and size of his cash gifts to American officials - has told a close associate that "the really big money always came out of the embassy."

There also are indicaitons that Ambassador Kim considered Tongsun Park a competitor to his own lobbying.

The indictment against Park, for instance, mentions that in 1971 then-Rep. Ricahrd T. Hanna (D-Calif.) - named as the recipient of more than $100,000 from Park - wrote a letter asking the director of the Korean Central Intelligence Agency to help resolve a dispute between the embassy and Park over "their lobbying and other influence activities in the United States Congress."

In an incident that has intrigued investigators, Rep. Larry Winn (R-Kan.) reported that shortly before the 1972 election a South Korean he had met only a few nights before at an embassy party here dropped by his office and suddenly handed him an envelope. The surprised Winn found later that the envelope was filled with $100 bills. An aide immediately tracked the donor down - in another House member's office - by asking the embassy where the visitor could be found.

Investigators from both the Justice Department and the House committee have been especially interested in that incident because the Korean had thrust a bundle of money on someone he didn't even know.

In 1974, John Nidecker, an aide to President Nixon, was handed an envelope containing $10,000 in cash as a "bon voyage" gift after he had attended a prayer breakfast in Seoul. The money was returned with a stern protest to a key aide of South President Park Chung Hee.

Nidecker also said that Ro Chin Hwan, a South Korean National Assembly member close to President Park, had offered to make donations to selected Nixon administration congressional candidates that same year.

Suzi Park Thomson, an aide to former House Speaker, Carl Albert has - despite a media blitz of denials on her part - been named in U.S., intelligence reports as a KCIA operative. Her role seemed to be to host small, informal parties where she could introduce her congressional friends to Korean diplomats, investigators believe.

Hancho Kim, another South Korean businessman who lived in Washington, was being groomed in the mid 1970s as a successor to Tongsun Park, who at the time was beginning to be the object of unfavorable publicity.

Investigators have been told that Kim was given $600,000 cash in two installments in early 1976. The money reportedly came through the diplomatic pouch from Seoul and was delivered by Kim Sang Keun, a senior KCIA official at the embassy here who sought protection from the FBI last fall and is now cooperating with the U.S. investigators.

Hancho Kim has denied the accusations.

While Thomson and Hancho Kim have been questioned by federal investigators, requests to obtain testimony from former ambassadors military attaches or other Korean diplomats have gone unanswered.

Justice Department officials never asked the Korean to waive diplomatic immunity in such instances, sources familiar with their deliberations said, because it was believed the Koreans would only be insulted and say no anyway.

The House committee made overtures about questioning diplomats to the Korean embassy a few months ago, but so far has received only offers to talk about the situation, reliable sources said.

Both Justice and the committee received some embassy bank records in the early part of their respective investigations, sources said. But more recently, the House committee especially has been rebuffed by attorneys representing the embassy.

Because under U.S. law such records belong to the bank, not the embassy, committee attorneys are known to be confident of winning any court test. But they hope to avoid extended litigation by the Koreans, whose American lawyers have cited the Vienna convention on diplomatic immunities as an argument against having those records turned over.

That agreement states that diplomatic archives, including financial records, are protected from another country's jurisdiction. The Koreans have said they will go to court, if necessary, to stop their banks from complying with committee subpoenas for such documents.

[TEXT OMITTED FROM SOURCES] with House Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.). The relationship was purely social, he said.

Asked why the interrogation concentrated on O'Neill, Park said he throught the prosecutors were anxious to clear the House Speaker of any connection with the influence-buying scandal.

"He is an important man heading the legislative branch and I feel we are obliged to the world and the American people to tell what the truth is, and in doing so I feel his name should be vindicated," United Press International quoted Park as saying of O'Neill.

Park sponsored elaborate birthday parties for O'Neill in 1973 and 1974. He denied reports that he had ever "operated out of" O'Neill's office.

All Seoul newspaper, which are under tight government control, printed the full text of the 30-page U.S. indictment against Park.

Agence France Presse reported that South Korean government officials described the indictment as an exaggerated list of charges devoid of any substance. It would have been rejected in South Korea, the officials said.

The same officials told AFP that the United States was using "undue and irrational" pressure in seeking the return of Park. They also expressed irritation over U.S. press reports that President Carter had sent a personal appeal to President Park Chung Hee asking for Park's return.

There were reports, too, that the Seoul government was concerned about the news that the U.S. House of Representatives had narrowly rejected a proposal to cut U.S. aid to Korea. It was feared the mood in Congress might delay U.S. military aid tied to withdrawal of American troops from Korea, APF said.