National Symphony Orchestra ticket sales were up this year, there was a $1 million subsidy from the feds and executive director Henry Fogel said the symphony will net more than $300,000 to apply against its $2.7 million debt. So it was disappointing when Rep. Sidney Yates' (D-Ill.) House subcommittee last week recommended a $350,000 subsidy for next year. "You can say it's a blow; or, that it seems to establish a more regular assumption than in the past that there is an obligation by the federal government to support arts groups in Washington," Fogel said. But there's nothing regular about the subsidy. If approved by Congress, it will be a one-shot deal. A congressional source who asked not to be identified said Yates had been reluctant when approving this year's $1 million because the symphony got a $1 million subsidy in 1981. "He was really giving it to them in the beginning as a stimulant, something to get them over the hump, and he feels they're on their way," said top Yates aide Mary Bain. She said symphony president Leonard Silverstein, a member of the President's Committee on the Arts and Humanities set up to encourage private giving, "should be taking the lead on getting more money" from the private sector.