Have a look at Vauxhall Vectra seats ... I was the other way ... Vectra seats are awful for me, but Landy seats (Disco) are awesome ... maybe it'll work for you in reverse!!!! Dunno if they'll fit, but a seat's a seat and ought to be able to be made to fit on another frame.
Try someone elses seats? Maybe yours have just seen there day as all the ones I have sat in are fine. I have 2 sets of cloth ones in ok condition as I have upgraded to leather, I was going to list them on ebay. One pair have fully working lumbar suport as I found whilst trying to move the seat in mid flight!
