I wouldn't be surprised if AZ had far more such guns than we do in VA. Anyway, this was a demo model that the local rep. from Sigarms brought to an IDPA shoot. I think they are only sold to military and police agencies.
AFAIK, private citizens in the US cannot buy any full auto gun made after 1986 and so you can guess that the ones we can buy are insanely expensive. A real M-16 is north of $15k. I've seen other class III guns for $40k when they cost $800 back in the day. A real Tommy gun was $125 back before the 1934 ban. You could buy a nice Porsche for what they cost now. Contrary to popular belief, machine guns in private hands are almost non-existant and those who have them are rich and well-regulated by the BATF.