Posted By:
Brad Green
Lefty Grove: 1941 Double Play (w/ Bobby Doerr)
Of course, Lefty retired after the 1941 season. So... he doesn't exactly meet your criterion of retiring BEFORE 1941, but I'll add his name to your list anyway.
If having more than one player on the card violates one of your unspoken rules, then his last card would be his 1937 O-Pee-Chee Batter-Up card.