260's were only sold for one year in the US but I wouldn't necessarily call them rare. There's a lot of them out there and they have a great deal in common with the 240Z and 280Z. Take a '73 240Z, add in a few refinements and extra seats of a '75 280Z 2+2, there ya go.
Actually, something like 75,000 were sold in the US that year. So rare...
I mean, rare is like a LHD 69 Toyota 2000GT with Air. One of 9.
That's rare, for a production car actually sold to the public!
Whacha need to know.
The 260 is rare in that it was only made for one year but in that one year it sold more than any other first gen Z. This is the best darn web-site ever but I also like Datsuns.com. A lot of Z specs, plus some great general auto info in the tech articles.