The AH Fox should be a 'Philadelphia' Fox. By that I mean the bbl address should say that.
BBl length makes a difference of late in value.
The 'must have' lately for the SxS set is long bbl's. Short bbl's are not in vogue at the moment for reasons unkn.
The shooters what 30, 32" bbled SxS's.
The 26" bbld guns are in less demand.
28" bbled guns will sell if priced right.
Buying it for yourself, the above can make no difference at all.
Fox never marked what chokes the bbls were. But obvious alterations are not appreciated by most buyers.
The 'bbl weight' is indicated on the bottom of each tube just ahead of the bbl flat on the bottom. #1 thru #4. Sometimes hard to read as the numberwas stamped before the tubes were final struck (filed down) for weight). #1 is the heaviest,,#4 is the lightest weight bbl.
Fox 12ga chambers were cut 2 5/8" at the time. They purposely cut them to that length for the 2 3/4" 12ga shell. They felt it gave better performance and pattern.
A true English stock should have a full length 'tang' on the trigger guard with the hand cut ser# in place.
Often if a gun is altered outside the factory from a pistol grip stock to a straight grip, they will just take the orig short tang pistol grip guard and straighten it out and reinlet it.
The short tang TG is a giveaway to an after market straight grip stock job on a Graded AH Fox.
IF the ser#'s match on the frame. forend and bbls.,,the butt stock is a true Factory English straight grip stock and not an aftermarket alteration,, the mechanics are excl'nt with no issues (safety works, bbls are not 'Off Face", bbls are not cut and are orig length,,no refinish to the metal or the wood surfaces...
Then the AH Fox is worth about what the asking price is for the 2 guns.
That's a retail price. You won't get that $$ taking the gun to Cabellas and flipping it for cash of course. But a true90% orig condition A-Grade extractor Philly AHFox in 12ga w/a Factory English butt stock and orig butt plate (the straight grip stock would have been special order) will usually get priced betw $1500 and $2000 on most dealers tables at a gun show.
Add Ejectors to the mix and the gun would skip upwards another $500 to $700.