After searching for 30 years, I finally found one in an antique store. I always make it a point to tell people what I seek. I had to make a follow up appointment, but it was worth the wait at only $500. My understanding is that these fetch over $1000 in demilitarized condition. This one was demilitarized with a bar welded across the barrel and a hole cut into the chamber. That makes it just a hunk of steel to the US Government and not a weapon. These fall into the category of a destructive device according to the Federal Government which requires the right paperwork to own. Right next door in Canada, they do not even consider it a weapon.