That's a great catch, Rhett.
I'm the last guy to talk to about Topps cards, but I remember reading somewhere that some of the Topps sets were actually produced by two different printers. There were subtle variations in some of the card images or border colors as a result.
This seems like it could be a similar situation. If it is, I would say that if there's one variation like this, there are others.
-Al
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