The Pershing II missile that President Reagan wants to deploy in Europe late this year won an important vote of confidence in Congress yesterday as a House Appropriations subcommittee agreed to release some previously held-up production money.

Congress last year held back $493.3 million in Pershing II production funds because the missile was failing flight tests. It invited the Pentagon to seek restoration of the money once the missile's performance improved.

The Pershing II is one of the main points of contention in the intermediate-range arms control talks under way in Geneva.

Defense Secretary Caspar W. Weinberger told the House Appropriations subcommittee on defense last week that the last seven tests of the Pershing have been successful and that continued production was therefore warranted. He has acknowledged, however, that Pershing II has not yet undergone a full flight test.

The Pentagon is requested $478.6 million in fiscal 1983 supplemental funds to keep the Pershing production line from being interrupted this year. Subcommittee Chairman Joseph P. Addabbo (D-N.Y.) told reporters his panel voted 7 to 5 to approve all but $25 million of that. He predicted the full House would go along.

Shortly after the House subcommittee vote, Weinberger went before the Senate Appropriations subcommittee on defense to repeat his pitch for the Pershing funds. He warned that it would cost $150 million in termination payments to the contractor, Martin Marietta Corp., if production were interrupted, and would delay full deployment of the missiles in Europe by at least 19 months.

"Such a gap would be perceived both by the Soviet Union and by opponents of NATO's plans within western European societies as a weakening of U.S. and alliance resolve," Weinberger said.

The defense secretary in the fiscal 1983 supplemental request also asked for $9.67 million to help pay a force of 93,000 West Germans who, in wartime, would guard U.S. bases, truck ammunition and fuel, repair air fields and handle prisoners. Weinberger requested another $5 million to store ready-to-use equipment in Europe for U.S. Army divisions and relief from the legislative restrictions on buying specialty metals from NATO partners.

The Pentagon's victory in the House subcommittee on the Pershing yesterday followed a defeat in the House Armed Services Committee Tuesday. That panel voted not to allow the Army, Navy, Air Force and Marine Corps to grow by 37,300 men and women between fiscal 1983 and 1984, and instead freeze the services at present levels to save money.

"It's unfortunate," Weinberger said of the troop freeze in reading a prepared statement at the opening of a hastily called press conference at the Pentagon. "It would reverse the major gains that we've made over the past two years in trying to bring our forces into a much higher state of readiness to meet any emergency, and it will have a long-term effect because it denies us the personnel that is really needed to help operate a lot of the new systems that have been authorized by Congress within the last two years."

While freezing the active duty forces at fiscal 1983 levels, the House committee voted to add 7,000 people to the Army National Guard. Weinberger said this would make the savings from the freeze "illusory" because the Pentagon might have "to add additional civilian employes to deal with some of these problems."

He said the manpower freeze, if sustained by the rest of Congress, would reduce readiness of forces to fight and amount to going back "to the old way of doing business."