Yes I was referring to those barrel converters by many manufacturers, the parts can fit in a xlr. And in the mic body if you are clever.
My guess is those modified mics on the used markets are done like that. If you change the innards of a 416 you get a new mic with
worn body and misleading markings, heh, btw if they sell the electronics and capsule assemply to you, you can put it in in couple of minutes without any tools other than a screw driver
Matti