I'm not an expert, but sounds pretty high to me, at least for here in the US. I sold a very nice M39 about 1 year ago for $550, and it was one of the harder to find late date "no name" or "ghost" models. Here is a listing I saw earlier this year that sold for $485 including shipping: 1944 Finn M39
They are very nice shooting rifles by the way. Sort of wish I still had mine, but my eyes and iron sights don't get along anymore. Good luck finding one.