Phil Woosnam, commissioner of the North American Soccer League, said yesterday that keeping a Washington franchise in the league is a major priority and said he would "turn every stone possible in the next 10 days" to find a buyer for the Washington Diplomats.

Madison Square Garden Corporation, owner of the team the last two years, decided in the last week to sell the club. Steve Danzansky, team president, is trying to put together a group that would purchase the team and keep it in Washington.

"I talked with Steve today and asked him how I could help him," Woosnam said. "I told him we would very much like to see local ownership by the team. s

"I also have to think about the best interests of the league. But I think it's very important that we have a team in Washington. If that means having ownership from out of town, or a combination local and nonlocal, then I'll try and put that together."

Woosnam said he plans to get in touch with all groups that heve expressed interest in owning an NASL franchise between now and Nov. 14, the date league owners will meet in Chicago. At that time Sonny Werblin, Madison Square Garden chairman, is expected to announce his intention to sell the team. Woosnam also said that as early as six months ago Werblin had met with representatives of Warner Communications to discuss the possibility of placing a franchise in New York's Shea Stadium. Warner owns the Cosmos and would have wanted a huge indemnity fee for his consent in allowing a second club into the New York area.

Woosnam said that negotiations were reopened beiefly last month, but that the two sides did not come as close to an agreement as they had in April.

"I think Sonny would have liked to have had his entire sports empire in New York," Woosnam said. "If things had worked out with the Cosmos he might have moved the Diplomats to New York or he might have bought another club and moved it there. It didn't work out and I am sorry that they are leaving the league."

Neither Werblin nor Jack Krumpe, Garden executive vice president, was available for comment yesterday.

Woosnam said that he is determined to keep Washington in the league for two reasons.

"The first one," he said, "is simple: it's one of our best franchises. Second, it's very important for international purposes. We put on a very impressive show for a lot of people when we drew more than 50,000 for the Soccer Bowl in September. If we want to get the World Cup here, Washington would clearly be a key city. We need a franchise there."

Until a month ago the future of the seven-year-old Diplomats seemed secure. Thanks in part to the purchase of Dutch superstar Johan Cruyff, attendance at RFK jumped this season to an all-time high of 19,205 per game. a

But escalating costs increased Madison Square Garden's deficit during its ownership to $5 million. That, combined with the team's location, apparently forced Werblin and Krumpe into this decision.

Whether Danzansky will be able to raise the money to buy the team by Nov. 14 remains a question. Because the team's losses were large, investors likely will be difficult to find. Danzansky does have two major selling points -- a recent upsurge in soccer here and Cruyff, who is still under contract, although new ownership would have to negotiate with him.

"It certainly isn't going to be easy," Woosnam said.