Posted By:
Judson HamlinThere seems to be at least two agents of the Saturday Evening Post who stamped the back of these cards, which are all 150 series. Is there anything to support a tie-in to the magazine, such as a distribution deal or (admittedly a reach) could these even be considered a formal overprint? Option (c) is just that these two guys were collectors independent of each other and used their work stamps to mark their cards.
edited to note 150 series