I bought some of the £9 ones last year,they were crap,very bad fit...looking at the others they look to be the same shape,probably best trying to find someone to make some
 
Don't think it's advised to fit seat covers to cars with airbags in the seats iirc! If you can live with it mabbe just get some of those plastic jobbies mechanics use? Then you can just throw them away when you're clean!