I was searching for BMW stuff as I am known to do and stumbled upon these guys who repair and make custom seats.

I have no idea what they charge.

Australian Comfy Seats

G'day Rossco , when my Corbin split I tossed up between recovering it or getting the original done , as I'm not doing so much long distance stuff these days I decided to recover the original , ACM did it exactly the same as the picture in the link ( standard width though ) great job , very plush compared to the washing board Corbin , it cost me $380.00 , had to get him to re-do the middle bit coz it had a few ripples in the vinyl , all good now .

Metcruze here in Dubbo does seats........rebuilt my seat on the naked.