In 2001, General Dynamics bought Santa Barbara Armaments from the Spanish government. Santa Barbara was the actual manufacturer of the guns sold through Marathon Products (until Marathon went under in 1987). If you can't find parts through Numrich, at http://www.gunpartscorp.com/ you're probably stuck. In perfect condition, these kit guns are only valued at $55, according to the Blue Book.
Probably not anywhere. I have been searching for ever for a stock for my Marathon First shot .22. Nobody has parts.
Numrich gun parts
you can find parts for your Stevens at bob`s gun parts .com
We have parts for that model. email@example.com
Check with a gunsmith, or find the model number of your rifle, and check on line parts supply houses, like gunpartscorp.com
Try Nurmich Arms
Numrich Arms is a good source for gun parts.
Go to Numrich Gun Parts Corp.
You will have to contact SIG to find out.