There are a lot of high quality homemade emblems out there, but Doctor Mego's in the only factory made version. It's a paper die cut. Original mego Cap never came with a paper emblem, only cloth and felt.
Both DM and CTVT have made boots. DM's are a thicker plastic, more round around the edges and stamped DM on the bottom. CTVT's are closer in thickness but are also slightly different in shape. They are unmarked.
Cap's shield is black plastic with a sticker on the front. There are some nice looking, in scale blue plastic shields from another line out there that can be mistaken for mego. There are no factory made reproductions available, but there are a lot of high quality home made stickers for the shield that have been made. More common than a repro shield, is an original shield with a new repro sticker. An original mego sticker looks kind of rough. The print quality is a little fuzzy around the edges, and the sticker itself doesn't lay perfectly smooth on the shield. This can lead one to think they have a reproduction, when in fact, they have the real deal. Original shields comes with both a glossy and a flash finish.