I know a lot of people have been sucessufl in getting second hand std springs at sensible prices. As they are heavy it makes sense to ring the known specilist breakers and go to the spares days as you will need to pick them up anyway. I like e-bay but for heavy things you can end up with long drives. I live in Slough but got a rad off e-bay in Stockport, that's 400+ miles for a £12 part. It was worth it because the second option was £210 but it pays to search locally first.