Everyone needs one, and the original profile seems to work better than any of the attempts to use other sections. Whatever the old source of EPDM rubber seal vanished into the mists of time. I had a company create a new die, and they can extrude an identical item in silicone rubber. Unfortunately they are only interested in producing it in runs of 100metres, so if you want one, you're going to have to go the route that I did, followed by Jimcub, and collect enough other people to use the run and pull the costs down. (You need 7 metres per car)

Contact details are:

Viking Extrusions
Ivy Arch Road
WORTHING
West Sussex
BN14 8BX
UK

tel: 01903 205 532
website: http://www.vikingextrusions.co.uk/
email: sales@vikingext.co.uk

The man who 'knows all about it' is called Keith, who is probably the one you'll get if you ring sales anyway, just mention my name (Alex Thompson) and Nova Club roof seal and he should remember what you're on about!