They USED to be common in the 60s-early 80s.
Just look at older British and German cars (HECK, the 1950s Mercedes SL sports cars had them).
I'm not sure the best material, but P/V might be ideal. It was designed as an upholstery fabric originally, but was found to be useful for kilts too. I guess it should be good for car seats.
Rocky thought it might work when I mentioned it to him a while back.

Of course, it would have to be a custom.