If possible, visit the gun auction website Gunbroker.com and search some of the ongoing auctions for the same or similar model.
If a registered member, it's also possible to search all completed auctions during the last 90 days to see what an item sold for.
I searched current auctions for Winchester 1894 and sifted through them for the .38-55's and skipped several.
I didn't look at any completed auctions to see the actual selling prices for those recently sold.
There's a mint 1894 .38-55 on there now for $2500 or $2700 buy it now:
http://gunbroker.com/Auction/ViewIte...Item=141372556
Another with tang sight and 85% blue is listed on reserve with an opening bid of $1400:
http://gunbroker.com/Auction/ViewIte...Item=141436543
Another is buy it now for $1750:
http://gunbroker.com/Auction/ViewIte...Item=140900401
Another is listed with no reserve at $1499:
http://gunbroker.com/Auction/ViewIte...Item=140939281
Another minty one is listed at $2900:
http://gunbroker.com/Auction/ViewIte...Item=140940117
Another is fair, working cond. with a round barrel for $1350, or $1400 buy it now:
http://gunbroker.com/Auction/ViewIte...Item=141003846
Another round barrel is $2400:
http://gunbroker.com/Auction/ViewIte...Item=141028059
Another 20 inch carbine for $1099:
http://gunbroker.com/Auction/ViewIte...Item=141142680
Another 26" octagon is $1100 - $1200 buy it now:
http://gunbroker.com/Auction/ViewIte...Item=141184405
Another is exceptional with Lyman sight for $3300:
http://gunbroker.com/Auction/ViewIte...Item=141363673
Another 20" carbine is $1495:
http://gunbroker.com/Auction/ViewIte...Item=140710134
Another 26" octagon for $1295:
http://gunbroker.com/Auction/ViewIte...Item=140710239
Another 26" octagon on reserve starting at $1250 with $1475 buy it now:
http://gunbroker.com/Auction/ViewIte...Item=141483761
Another is special order with 20" octagon at $3300:
http://gunbroker.com/Auction/ViewIte...Item=141553468
Another 26" round with Lyman peep for $1495:
http://gunbroker.com/Auction/ViewIte...Item=141393910