I think it's called inflation. I quit buying 5 screw M28s when they started to cost more than $250. Now at the central Texas gunshows any halfway decent 28 seem to be bringing around $1200. The $50-$75 M10s are $450 and up, older ones are even higher. All I can say is I'm glad I bought some fairly rare Smiths when they were released : 53s, K32s etc.
SWCA 892