Buy parts for 410 Stevens model 67 pump shot gun.
I have parts for that model. email@example.com
Check on Numrich gun parts corp website.
Riverside was manufactured by Stevens, so if you can identify the equivalent Stevens model, you should be able to find parts. Check with a local gunsmith.
Numrich Arms should have them.
A FEW parts are available from gunpartscorp website.
Numrich gun parts. Parts availability depends on if you have an old model or new model. There is a nice schematic on their website listed under Stevens 101-7
I would try Numrich gun parts corp.They may be found on the web.
The 238 is similar to the 258. For parts, try gunpartscorp.com
I am not sure about the diagram,but I would check at numrich gun parts corp. first for the parts you need.
Try your local gunsmith. The Riverside is a Stevens shotgun. If you can find out which model it is, you can probably find the wood at Numrich Gunparts