Posted By:
Marc S.I've been corrected/informed from a very knowledgeable collector that this is not actually an unpublished Topps card.
Rather - this Madlock is what was used in the 1977 O-Pee-Chee issue. Unlike previous OPC issues, there were a few corrections in the 1977 OPC issue, including Madlock, Murcer, and all of the Blue Jays....
Hope this helps.
Cheers-
~ms