Here is input and advice: * Having owned this gun many years ago, and having paid $300.00 plus for it, I would think it would be worth at least as much as I paid for it. I would certainly not take less, because this gun survived a house fire, mechanically perfect, losing only the forearm and stock. My real bad luck was that someone came into my burned out house, and stole the rifle. My estimated value of your rifle: $300.00 in excellent shape. * I just bought a 39A Mountie at an auction. Was intrigued with it because my Dad bought one on his 19th birthday, and still has it. I paid $300 for it at the auction, and think I got a good deal. * Condition, condition, condition. In excellent, 100% working condition, a 39A is currently going for at least $375 in most locales. New price is close to $500. But, if it has rust, damaged wood, missing parts, or a bore that does not clean up, you can expect the value to fall fast. BTW, a firearm in a house fire is probably damaged beyond any reasonable repair attempt, as the fire destroys any heat treatment in the steel.
Just bought a 1976 model 39A for $325 - not a great price, but OK. It had some minor surface rust and some scratches on the stock. They are good guns that hold their value well. I like the older ones without the crossbolt safety and the rebounding hammer. I also think the checkering on the new ones is a little gaudy, but to each their own.