I have 500606, it is a 32" barreled, double trigger, splinter forearm, with a Hawkins Pad. It is the later type NID frame with the stippled top, no dog, and no indicators. All is original with a ton of case colors, blue and nice wood and checkering, it is probably around 95%.
I did have the forearm repaired, it had split on a line following the ebony tip.
They are great goose guns and work fine for ducks as well with some 2 7/8" Bismuth hand loads.
I wouldn't want to have to carry it very far though, boat to blind is fine.