ORIGINAL: bigbulls
#1. you don't have to shoot 3.5" shells when you go goose hunting. A 2.75" 12 ga shell will hold the same weight shot as a 3" 20 gauge shell. Choose a smaller size shot for a denser pattern at longer ranges... maybe something likeheavyshot #2's.
#2. A 12 gauge gun will be heavier than a 20 gauge gun of the same make and model so the extra weight will help with recoil.
#3. You didn't say what shotguns you have but you should be able to install at least one mercury recoil reducer in the gun and probably two. One in the stock and one as a mag tube cap.
#4. you can get any make of recoil pad for as shotgun as you can a rifle.
Sorry to here about your troubles. As stated above BigBull has pretty much nailed it on the head. I will also say that a limbsaver pad will reduce felt recoil as good if not better than any of the other after market pads. Also as stated from anothe post 2 3/4 shell loads will cleanly kill as well as the super mag 3.5 loads. Now I'm telling you it is a mind over matter issue and it improves your shooting skills and protects your wallet a heck of alot more, too! JMO
Hope things go well for you under the knife. You may find that shouldering and swing is alot more of a limiting factor from some of the other people I have dealt with over the years that have had this type of surgery? Not trying to scare you jusr want you to know there are other drawbacks that might occur?
Again good luck and if I can help, don't hesutate to e-mail me.