Dan,
"Proofed" in the case of your gun, is likely going to be limited to your gunsmith taking the gun to a trap club and using it for a round or two of trap, sporting clays, or skeet, should he choose to undertake the repair.
There is no organization or law pertaining to proof in the United States. Europe clings to a proof system, which, pretty much assures that a gun will have a bunch of stamp marks struck into the flats or on the sides of the barrels, and further assures someone that the gun passed proof on a given day. There is no assurance the gun could do it again, even the next day. Failure of guns, proofed in Europe, or, unproofed here in the States, is a pretty rare event, and is usually related to things beyond the control of the proof house anyway, a stuck base wad or plugged bore being about the most common, it seems. American guns, proofed and used in Europe, don't fail proof at higher rates than European guns, which would seem to point in the direction of American gunmakers and gunsmiths knowing what they are doing.
If you don't fix it, consider donating the gun to a gunsmithing school. It would likely either be repaired, or, it's parts used to repair others. That ends the problem of someone after you dealing with a potentially catastrophic failure, and is much less brutal and wasteful than the "hacksaw" method employed by my father.
Good luck.
Best,
Ted
