It appears that Trans-O-Gram was a major toy maker in the 1960's; who specialized in kids stuff
This is an item in an Hunt Auction with an endorsement from Mays and Mantle.
http://www.huntauctions.com/online/i...=401&lot_qual=
It was incorporated in 1959
http://www.scripophily.net/trcoinpe19.html
And my guess; and I have no knowledge of anything on this -- was that during the late 1960's -- the MLBPA were really starting to realize that they could make money on cards with the player's group and thus looked for new products to have cards made on. Trans-o-gram, with their history of baseball products; probably thought they could make money with the players' images on cards just as for example, Post Cereal did from 1961-63.
I could be wrong; as this is just an hypotheses. Perhaps Mr. Hornish or Mr. Lemke have covered this at some pt in their research.
And Bill, STAY as WELL as you can be, I know how important all this relief is to you.
Regards
Rich