Paying the price for finishing highest among nonplayoff teams, the Washington Capitals twice saw coveted youngsters claimed by others before they took Kitchener defenseman Scott Stevens in the first round of yesterday's National Hockey League entry draft.

In an attempt to recoup, the Capitals committed themselves to a modest investment of draft choices and salaries to obtain veteran Czech center Milan Novy, Calgary goalie Pat Riggin and right wing Ken Houston, and Buffalo winger Alan Haworth.

Along with the selection of Stevens, General Manager Roger Crozier was able to say at day's end that, "We have five guys today we didn't have yesterday who are capable of making a big contribution to this club next season."

The Boston Bruins were even busier than Washington, as they began a day of surprises by relinquishing everybody's top-rated pick, Kitchener right wing Brian Bellows, to Minnesota for winger Brad Palmer and center Dave Donnelly. Then, after selecting blue-chip defenseman Gord Kluzak of Billings, the Bruins shipped defender Brad McCrimmon to Philadelphia for goalie Pete Peeters.

Toronto chose defenseman Gary Nylund of Portland, the third sure-fire prospect on the draft list, before the Flyers soured Crozier's coffee by picking center Ron Sutter of Lethbridge. Sutter, the man Crozier wanted badly, had not been mentioned in predraft speculation out of Philadelphia.

After requesting a brief timeout, Crozier selected Stevens, who played the left side for Kitchener's Memorial Cup champions. Stevens could be a good one some day, but has played only one year of junior hockey. If he sticks in Washington this fall, it probably will be as a sixth defenseman getting spot duty for the sake of experience.

The day's four veteran acquisitions, on the other hand, figure to move into regular roles if they can live up to past performances.

Riggin and Houston were obtained from Calgary for defenseman Howard Walker, who did not figure in Washington's plans; left wing George White, a 1981 draftee from the University of New Hampshire; a sixth-round selection yesterday, a third-round choice in 1983 and a second-round pick in 1984.

Two spots before Crozier planned to take Regina defenseman/winger Gary Leeman in the second round, Leeman was selected by Toronto. So Crozier dealt his second- and fourth-round selections to Buffalo for Haworth, a No. 3 and a No. 12.

With that third-rounder from Buffalo, Crozier chose Novy, 30, the all-time Czechoslovak goal-scoring leader with 430. For the first time this year, all Europeans, regardless of age, were required to go through the draft process before joining an NHL team, and the Capitals must negotiate Novy's release from the Czech Ice Hockey Federation before signing him.

Novy, a regular on Czech national teams for the past 10 years, reportedly wants to play in the NHL and had put Washington high on his list because of the presence of the Czech Embassy.

Later, in the 10th round, Washington drafted center Juha Nurmi, 22, a member of the Finnish national team.

In Riggin and Houston, Crozier could be picking up some problems along with demonstrated talent. Riggin, 23, has been a pro four years, since joining Birmingham of the World Hockey Association as an underage player in 1978. Although sometimes sensational, he is both streaky and temperamental. He has been known to throw his stick at a coach who yanked him from a game and exchange words with critical fans.

Houston, 28, has suffered from chronic hepatitis and has never scored more than 23 goals in a season, although he can be a crunching checker at 6-foot-2 and 207 pounds. His good health has been guaranteed by Calgary General Manager Cliff Fletcher, who agreed to renegotiate the trade if Houston cannot play.

"We know there are some problems, but we think we can straighten them out," Crozier said. "Sooner or later, we had to stand up and take chances on some guys. If we never take a chance, we'll never get ahead. We've got to create some interest here and let people know we're trying to do something."

Haworth, 21, impressed Bryan Murray when the Capitals' coach was in Hershey and Haworth toiled for Rochester. Haworth collected 21 goals in 57 games for the Sabres last season.

"He has great speed and he's young with what we consider a great future," Murray said. "He could be second fastest on the hockey club behind Mike Gartner. We'll try him at left wing, but he gives us depth because he can play all three forward positions.

In a related move, the Capitals signed Brent Pascal, a 6-2, 217-pound winger who played for Murray at Regina in 1979-80.

"He's tough and aggressive, and he should push a few people to make the hockey club immediately," Murray said. "Houston is big and strong, too. We need guys like this to give others the chance to play our style without being intimidated."