That's an early 686, while I generally think speed loader cut checkered target stocks on a 686 yours is early enough that my bet is SW probably still had some football cut smooth presentation stocks hanging around if not at the factory definately at local gun stores for people that wanted fancier stocks,
Also those presentation stocks appear to be late production solely based on the big football cut and wood color so likely at the very end of the football cut era so not really a big mismatch if any but thats just IMO.
Wondering what your prefix is since you know its an 81, IIRC we had someone post a 581 with an AAA prefix yesterday, don't see a whole lot of the AAA prefix guns posted.