Brian,
there was only one CSM at the Julia Spring auction,it was a FE 28ga w/26 in Krupp barrels (Lot 1396),it sold for 19550 (including the vig) against a est of 17500-25000.

I think the main reason you don't see many is most of the guys that buy them have enough money that they don't "have" to sell them.New,they keep going up in price so no reason to sell.

Keep Safe and thank you for all you do for this country,
Dave

Hillary For Prison 2018