Also don't discount the K11 or 1911, they go for a bit more money but if you find one for the same money don't pass on it.
The best way to get a K31 cheaper is go to a gunshow or Cabala's, somewhere with a rack of them and find one with a horrible beaver chewed stock and perfect metal. I have seen some real ugly ones for like $190, but the stocks refinish real nice and you have a pretty rifle. The older rifles for some reason seem to have nicer stocks.