This is a long shot, but this seems like a good place to ask...
In the 1950's-1960's (?) Champlin Firearms converted M-1 carbines to .357 magnum for the Oklahoma Highway Patrol. I am currently looking to buy one.
Has anyone ever seen a Champlin carbine like this? Any members of the Oklahoma HP remember seeing these carbines? I would be interested in finding one, but it must be a Champlin conversion.