A federal grand jury here yesterday indicted four oil companies and five oil men on charges of participating in a "daisy chain" oil-pricing scandal.

Among those indicted was The Crude Co., of Casper, Wyo., which is headed by Marvin K. Davis, one of the nation's richest independent oilmen.

The 29-count indictment accused the defendants of selling "old" domestic oil, that is, oil pumped from wells drilled before 1973, at higher "new" oil prices.

Uni Oil Inc. of Houston and its president, vice president and secretary-treasurer were indicted, as were two companies reportedly controlled by those officers registered in the Grand Cayman, British West Indies.

The Uni Oil officers had also been indicted for illegal oil pricing in an 87-count indictment returned in March.

Also indicted were John Allen Masek, a Crude Co. officer, and R. Stanley Corbitt, a purchasing agent for International Petroleum Trading Company (IPTCO) of Houston.

The indictment alleges that between July and November 1976 the defendants conspired to sell IPTCO more than $850,000 barrels of old oil illegally certified a new oil.

Meanwhile in Tampa, Fal., four oilmen were sentenced to three years in prison for their roles in a 1973-74 daisy chain swindle that caused Florida Power Corp. customers to be overcharged on electric bills.

John L. Burns, James R. Clark and Ronald B. Pruitt, all of Houston, and Walter L. Ballard of Ford Myers, Fla., are expected to begin serving their time nine days from now unless they win a delay through appeal.

The four were convicted in March following a month-long trial in Jacksonville. During the nation's energy crisis five years ago an interrelated chain of Texas companies traded fuel oil on paper over and over before Larcon Petroleum inc. finally sold it to St. Petersburg-based Florida Power. With each sale the price of the oil was escalated.