The standard recommended parts houses of Numerich gunpartscorp.com
Jack First jackfirstgun.com
Bob's Gun Shop gun-parts.com
may be able to help. I don't recognize that brand.
You could check midwayusa.com. If they don't have what you're looking for, I would suggest going to a local gunsmith.
Try MidWest Gun Works
Good luck. Try e-gunparts.com
try gunmaker.ca
Check under the forearm
duuno if u find out email me at jcm_42@yahoo.com
Shotgun News, gun shop, gun shows, internet, want ads, e-gunparts.com
Try e-gunparts.com
you may find some info at the savage arms website.This was the maker of your shotgun,savage/stevens.
Mossberg....under the model number 500. I have the same 12ga shotgun, I would like to find out what years it was made and the value.
Library, gun shop, gun shows.
Take the forearm off, it's usually on the bottom of the barrels.