I remember new Norinco SKSs being $79-89 at the shows, of course at that time Swedish Mausers were in the same price range. So if the SKS are in the $300-400 range, it shouldn't surprise me that the Swedes are in that range too, if you can find one.
Where at that time, and still, could you find a brand new high powered semi auto in that price range? Fortunately, ammo is still relatively cheap.
Everything goes up, we just have to get used to it.