I don't know if he is still in the business of producing claw mounts but there is a website,
http://clawmounts.com/ that show very nice modern reproductions for sporting rifles. I believe he was a small supplier to Brownells for a very short time. I have a pair on a Winchester Model 70 in .375H&H. I've shot this rifle quite a bit and the mounts haven't failed.
I have a set of Steve's clawmounts on a custom 7x57 I had built on a 1909 Argentine action. They work beautifully and don't alter the action. He says they'll take recoil up to .375 level, which I don't doubt. Glad to hear a first person affirmation of this, though, as I'm considering a .350 Griffin & Howe next and would like to use his mounts again.
