AT THE MOVIES, Lee Marvin leads one of Hollywood’s all-time toughest tough-guy crews behind Nazi lines in The Dirty Dozen. IN MUSIC, Headquarters , by the Monkees (left), is No. 1 on a Billboard LP chart that includes the No. 8 debut of a little album called Sgt. Pepper’s Lonely Hearts Club Band. IN BOOKSTORES, Chaim Potok’s Jewish coming-of-age tale, The Chosen, is a New York Times best-seller. AND IN THE NEWS, as the Vietnam War escalates, the U.S. military reports that 274 Americans have been killed in the past week, nearly twice as many as in the seven days before that.