"Collector Value" has dubious meaning on English guns like this. Don't get me wrong, I love English guns. But they weren't made with the same published specs like American guns. I don't think anyone would open the chokes or put a pad on a documented Sousa Special because of the financial hit they would take.
On an English gun it's another matter. The English do what they need to to keep a gun shooting well for it's owner, including opening chokes, refinishing, etc. On your A&N I doubt there's any way to determine how it left the factory so trying to keep it original is not a concern.
And finally getting around to the point, if the hinge pin is the only mechanical problem spend the $200 to have it replaced correctly. SKB is doing one for me on a Francotte, not prohibitively expensive.
