I won't claim to be an expert - maybe $500 or so in really nice condition. Check for cracks in stock around tang area - that would hurt value. Seems like often the rifling is pretty worn on those too. They seem to get docked in value pretty heavily if not in really nice condition
My dad had one that wa the first gun i shot growing up. I bought one on gubroker about a year or two ago for the kids. Seller was not a gun person - she was selling off her father's guns. I paid about $300-$350 for it. Bluing was good, wood was relatively nice for one of these. A (young, presumably) former owner had done some very slight engraving that actually was kind of cute and didn't detract from it in my eye. Well, it had a very slight crack in the tang area, rifling was worn, and had horrible trigger. So it wasn't very accurate and the kids preferred 10/22. So I sold it. Think I got $200. Crack really hurt the value - I heard that from several potential buyers.
I think they are really cool, and if you get a shooter, it would be a great starter gun for a kid. I just had no emotional attachment to this one since it was not my dad's, and it wasn't a shooter, so it had to go. They aren't too hard to find on gunbroker, but in retrospect probably isn't the kind of gun I should have bought on there. It was my mistake. You could probably get a decent idea of value on there, though.