Get a plate made up from the engravers with DMC written on it like a pro-circuit job & weld it to the stocker,fake it for now till one comes up
My 85 CR125 had a crap steel non original muffler on it when I got it so off to Ebay I went & scored a way cool DMC oval muffler that needed a clean up & a new perforated core for a good price
so nobody does a pipe for that model? GMC would make ya one