Corvairs were a neat car. GM's answer to the Volkswagen.
I'm not sure if the early ones are worth more than the later versions. A 4 speed model is of more value and a Turbo Spyder is even more valuable. My brother had one. It was really quick and the trans was built with the same parts as the Chevy M21 4 speed. The M21 was used in all small block powered cars.
I do know the early models didn't know which end is up. They had a tendency to flip, see Ralph Naders book "Unsafe At Any Speed". He really killed the Corvair with that one.
There's lots of Corvair clubs around, search the net for them.