Cabela's in Kearney has several M-15's , M-10's & M-13's that are parkerized for $400 each. I assume they must be a prison or armored car company trade ins guns from somewhere? whoever cleaned them up didn't oil them at all and they feel really dry and gritty. my feeling is that any one of them is at least $150 too much. I didn't see any markings pertaining to a particular prison. some of the front sights were even painted.