have a vintage Benjamin air rifle model 312 in 22cal s/n H1xxxx barrel whats a good source for any details/value of this rifle?

https://www.airgunnation.com/

Lots of knowledge there. Ask and guys there will know everything.

Have one myself, nobody can pay enough for my first rifle. 60 years old and still shooting.

One of these? Mine was bought new about 50 years ago, has been resealed three times and has dropped a chitt pile of critters. Last reseal was just a few years ago. At the reseal the 'smith (local) had an OEM forearm replacing the "square" one I made in high school. He had quite a selection of OEM Benjamin and Sheridan parts. As above, it's going nowhere. Maybe a grandchild will get it.

just added a 310 and a 312 to the airgun selection. Bought both at a local auction and thought they would need seals but they both are good

Outstanding. I just guess us older guys keep our first air rifle or firearm as a memory to our youth. Kids don't seem to do or appreciate this anymore. I still have my Mossberg 22 I got 75 years ago.

I’ve resealed/repaired/restored dozens of Benjamin rifles. The 312 is my favorite Benjamin!
I sure see a lot of Benjamin airguns that have had a rough life of mistreatment!