There isn't any. You have to make your own. Same as making a slipcover for furniture. There's lots of good how-to books on making slipcovers.

I made some for my car afew years ago. Use newspapeer and cut the pattern the same as the seams on the existing seat. It takes some time but they will fit perfectly. I used swimming suit material on the backs to make it easy to put on and take off.

i've just been asked to make a seat cover and i get how to make the pattern but how do you attatched the cover once on to the base ( its usually metal or plastic )also what types of fabrics are suitable thanks