Dear DrewDavid from Maine,
It would be interesting to see how that gun cleaned up after being submitted to a good wirebrushing and crosschiselling.
IF IT MEASURES WITHIN THE PRESCRIBED DIMENSIONS AS LAID DOWN WITHIN THE RULES OF PROOF, legally it is permissable to sell it and / or shoot it.
It looks rough at the moment but who knows how it will clean up.
Many a gun that is now the pride and joy of a Yankee started off in much worse condition than that.
'Caveat Emptor' but nothing ventured nothing will be gained.
TLC for TLC
Tender Loving Care for The Loose Cannon