That beautiful old Winchester certainly has 5 digit potential, especially if sold through one of the higher end auction houses that allow Internet and phone bids. They may charge a sellers premium but it usually well worth it. A little research on Find Live & Online Auctions for Antiques, Art, Cars & More at AuctionZip.com may help you find a place in your area to fill the bill.

Some auction houses will post results of past sales on their web sites. By way of example, one such place here in Pa is Morphy's, located in south eastern Pa. They devote several of their auctions each year to firearms and related items and always have results posted within a week of the sale end. Take a look at Past Antiques Auction Results | Morphy Auctions
and browse through the past results and you may find some similar Winchesters listed.
I wish you friend good luck. He certainly has something special there.

John