How to replace D7100 memory card door
Replace D7100 card door
crwdns2934109:0crwdne2934109:0
Replace D7100 card door
crwdns2934109:0crwdne2934109:0
If you don't get a better answer, here's the parts list that may give an idea of what to do.
In Fig.4 on p.5 it shows the SD card cover (part #1F999-551) and the SD card lid (part #1F999-552) and how they fit into the camera.
Search online for Nikon 1F999-552 to find suppliers that suit you best. (supplier examples only)
crwdns2934105:0crwdne2934105:0
crwdns2936751:024crwdne2936751:0 0
crwdns2936753:07crwdne2936753:0 7
crwdns2936753:030crwdne2936753:0 7
crwdns2942667:0crwdne2942667:0 7