The "professional" way is to TIG weld up the hook and fit the barrels from there. The "unprofessional" way is to use a feeler gauge to check the amount the gun is off-face. Then fit a shim to the hook that would bring the gun back on-face. You use grease as a release agent on the hinge pin and nearby metal surfaces and use green loc-tite to fasten the shim to the hook. Then put the barrels on the gun and close the action. Let it set for 24 hours and you should have a quick and cheap, although not permanent or sexy looking fix.
Let the flogging begin.
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