Originally Posted by
FBinNY
This is an option, but most accessories like racks and fenders have 5mm holes so he'd have to drill out whatever he's mounting. For about the same cost as buying a drill and tap, he could have a shop install a 5mm helicoil.
I'm with fietsbob on this one. If the OP can't restore the original threads using your suggestion, just drill the hole to clearance diameter for the 5 mm bolt (a 13/64" drill bit will do it) and use a longer bolt plus a nut on either the inside or outside of the dropout. There is plenty of clearance.
BTW, I expect the reason the OP damaged the eyelet initially was due to paint in the threads. When I built up my Cross Check with fenders and a rack, I had to spend a lot of time cleaning overspray out of the threads.