Both Washington-area singers who competed in the National Auditions Finals at the Metropolitan Opera in New York came out winners Sunday. Baritone Gordon Hawkins and soprano Susan Bender placed in the top 10 in the nationwide competition.

The contestants were judged by a panel of 10, but two surprise celebrities dropped by to help: virtuosos Luciano Pavarotti and Placido Domingo. The 10 finalists will perform in concert April 20 at the Metropolitan Opera House in New York.

Hawkins and Bender were chosen to represent this area in the competition by singer Anna Moffo from among eight local singers who competed at the National Gallery last month.

Chess' Kid Whizzes

Judith Polgar, a 10-year-old Hungarian chess whiz, won the $1,000 first prize in the unrated section of the New York Open chess tournament yesterday. Polgar won her first seven games and drew in the final round.

The champ's sister, 11-year-old Zsofia, competed in the Class A section of the open tournament, against players two levels below master strength. Zsofia was also contending for a top prize, having won six of her first seven games.

The girls were taught chess by their parents when they were preschoolers. "By the time they were 5 they could play blindfold chess," said their mother Clara Polgar, meaning they could play the game without looking at the board.

End Notes

Actress and dancer Chita Rivera, who has been starring in "Jerry's Girls" on Broadway, was injured shortly after midnight yesterday when a New York taxicab ran into the car she was driving, police said. Rivera, 53, is in satisfactory condition at Lenox Hill Hospital after surgery for the compound fracture of her left leg. will be replaced by seven showgirls who will divide up the star's numbers in the show . . .

French novelist Marguerite Duras, 72, was awarded the $50,000 Ritz Paris Hemingway Award yesterday for her book "The Lover" at a reception at the Hotel Ritz in Paris. The award is given to the best novel of the year published in English . . .

The London Post Office announced yesterday that Britain will issue a special stamp to mark the upcoming marriage of Prince Andrew and Sarah Ferguson. The stamp, which will go on sale eight days before the July 23 wedding, is being designed in consultation with Buckingham Palace . . .

Singer Rudy Vallee was in fair condition yesterday after two months at the Cedars-Sinai Medical Center in Los Angeles for treatment of throat cancer. It was believed that the entertainer might be released next week, but a hospital spokesman said he might be at the center for a couple more weeks. Vallee, 85, was admitted to the hospital Feb. 2 . . .

Alison Garner, 13, of Edina, Minn., arrived in Washington yesterday for a four-day visit that's her prize for winning the National Geographic Society's "Draw-a-Grotesque" contest. Her winning design, which has been carved in stone for installation on the Washington Cathedral, is titled "Sagacious Grotesque." It depicts a big-toothed grotesque holding an umbrella, protecting itself and the cathedral from rain . . .

Alabama Gov. George Wallace remained bedridden yesterday, under treatment for a hip ulcer. Wallace, 66, who announced last week that he would not run for reelection, is expected to return to work within several days, his press secretary said.