High grade Parkers are worth a lot and even the bottom grades are going high if mint. However, I don't have a clue as to what's worth what. I'd suggest asking over at: http://talk.shooters.com/room_56/current_page.cfm
and advise that forum as to grade, approximate serial number and any other features you see.
Jan, over at www.huntchat.com/ in the scatterguns forum Old lightning can post a lot of good info on the Parkers. He likes to see pictures and all the numbers you can cite in you post. A scanner will help. Good Luck on your venture.
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