It was made by the hand of man and, therefore, the hand of man can fix it to how it was.
The big questions are (a) is the game (fixing it) worth the candle (the price) and (b) will it be safe to use if it is fixed? AFAIK (and that's not very far) there is no way (absent destructive testing) to figure out the heating regime it went through to get to the point it's at and therefore no way to definitively know what kind of heat-treatment fixing might suffice to make it safe.
It might be most useful as an exemplar to use for making a new one, for the very-advanced home gunsmith/machinist. But that's my $0.02.
