Well, here in So.Cal, I do manage to see at least two or so every other week. When I go to military drill, I see them all the time. It depends where you go.
I can't find any 81 models, except for the one I found for Cold Case which I am sure they destroyed. Oddly enough, finding them on the street is become very difficult around here, yet I manage to see some new one I didn't know about that just comes out of nowhere. My guess is there are a few beaters left, but many more nice garaged ones waiting to be discovered and tagged for the club. I have been mainly looking at street corners where I drive and don't get much success there. Oddly enough, the Aries and Reliants I find almost always have body damage.