Hi Mike, the one on the right appears to be from 2017 Bowman's Buyback set (found among the inserts here). Because a formal checklist wasn't released, we've just been adding them as members send in IRs for them one (or more) at a time. To get yours added, please try to determine the color of the stamp, then go to that set's link from the link I included above, then click the "See any inaccuracies? Click here to let us know" link on the left. (Also, please note that above that, the Release Notes section tells you exactly what to do: "This checklist is a work in progress. Please use the inaccuracies reporting link for the set to report any missing cards. Please include the card year in the request.").
