Bob Barker is heading toward his last showcase, his final "Come on down." ADVERTISEMENT The silver-haired daytime-TV icon is retiring in June, he told The Associated Press Tuesday. "I will be 83 years old on December 12," he said, "and I've decided to retire while I'm still young." He'll hang up his microphone after 35 years as the host of "The Price Is Right" and 50 years overall in television. Though he has been considering retirement for "at least 10 years," Barker said he has so much fun doing the show that he hasn't been able to leave. "I've gone...