How rare of an oddity is this?

Found in a box of junk wax. Not a miscut because the front is intact. I guess its just considered a misprint. Not hall of famers but I think its cool they were both all-stars. Did a quick search but I didn't find anything about it. Really curious if its one of a kind...and wondering what to do with it. Is it worthwhile to authenticate and slab something like this? Is there a forum for people who collect weird stuff like this?