Get into premiums, team issues, etc.
There are a wide variety at various entry points. Or photos. Vintage snapshots are card-like and can be had for a fraction of the cost of a card. Some were even made by professionals with field level access:
Jimmie Foxx with the Cubs
Satchel Paige
Marshall Goldberg, college AS game, 1939
1961 Chamberlain, Russell, Cousy at the 'Gahden'.
Jack Dempsey sparring with Bill Tate, Toledo, OH 1919. Had to slip in a boxer
There's always something to play with, you just have to be creative.