It's difficult to say without seeing the gun, knowing the barrel lengths, chokes etc.
Once you stamp the name Winchester on anything the world changes. To some the gun would be worth no more than any Laurona in similar condition which is in the $500 to $700 range. But to a Winchester fan who believes this is a rare, European only Winchester that is very difficult to find then double those prices.
Put the flying red W on anything and rational thinking tends to fly out the window.