I too would prefer a 12 inch barrel over a 14 incher and from experience I know that the recoil without a scope is quite managable and with the weight of the scope should be even more so. You shouldn't need the muzzel brake.
As far as scope mounts are concerned, I would go with T/C's Weaver style mounts that you can get from Fox Ridge Outfitters. The holes in the barrel already taped for the scope should be sufficient. I would likely let the T/C Custom Shop do the work since that way, if something goes wrong, you have a lifetime warrenty to back everything up.
If you put the scope on yourself, make sure you Loctite the mounting screws for the base if you don't want it to shoot loose.