kd:
If you would consider a Holland & Holland I recently saw a nice backaction 12 with 2" chambers. I know the smith that has the gun and he already has received confirmation from H&H that the gun has original wall thickness and has not been altered. It is proofed for 15/16 oz and weighs 5 lbs 9 oz - the weight it was when it left the factory 75 or 80 years ago. Maybe 50% case color left. I want to say the fellow is asking $17,500.

Nice gun if the shot charge and backaction works for you.

Chicago Mike