I collect Yankees cards to include those of Yankees affiliates. I scanned a few. Some of these sets are very interesting- not only because of "pre-rookies" but for other reasons. In this era, minor league cards were sold at the ballpark for $3-5. At the end of the season, some lucky fans got free sets for "Fan Appreciation" night, which is the night where the team got rid of all the unsold memorabilia and stuff from stadium giveaways from the season.

In this picture-
a batboy, a Hall of Famer, a cool suit, a future manager, a groundskeeper, the grandson of a Hall of Famer, and 2 prospects.

In this picture-
a batboy, a Hall of Famer, a cool suit, a future manager, a groundskeeper, the grandson of a Hall of Famer, and 2 prospects.