Wow, that's pretty...sure you want to drill into that wood? How about a small back pack and/or a sandbag? I can't speak for a Diana, but I can say that my NPs shoot a little loose if I rest them on anything harder than my palm or a soft-ish bag. I imagine a bipod would have a similar effect (on my guns, anyway). Just something to consider if you're zeroing on the 'pod, but won't always be shooting from it. Is your gun's balance point near the trigger guard (common with break barrels, I think)? If so, I'd think you would would want to mount a bipod near there anyway (for recoil/consistency sake?). I may be waaay off base with this, but it may be worth researching/considering.