I know there used to be a Rewaco dealer in Las Vegas, not sure if it's still there or not - when I try to look at Rewaco's site, I get a message saying to contact the Canadian office. Try this link though - it has a link for email and a phone number further down the page.
You could also try Eagle Riders - they do rentals all over the US, and trike rentals in some locations. I don't see anything that you're looking for, but maybe they can point you in the right direction.