For sale is a VERY RARE, QUITE SCARCE complete (8 players) set of the 1988 Yankees/Mets Doubleheaders series, featuring miniature “proof” versions of the eight players’ Topps Rookie card on one side & 1988 Topps card on the reverse, in small plastic stand up frames. These are known as the 1988 “proof” Topps items, as […]