Ah, the power of the internet to bring people together.
If you figure that of the 586 original 1974 Duster 360 4M cars produced, only 70% remain (could be much fewer), that leaves 410 of them. Distributed evenly over the 3,797,000 square miles that makes up the USA, that puts one in about 9,256 square miles. That's maybe 7 in your whole state? And if 1 in 10 is ever taken to a show, that leaves a very small chance you would ever see one at a show.