Somewhere out there someone makes a rubber moulding that works really well. I had some fitted to a second hand set that I bought and they look like factory from the outside when installed, see post #3 here for the profile...
http://986forum.com/forums/diy-project-guides/65933-will-work.html
I have no idea where they came from though I'm afraid, I've searched the catalogues of a couple of rubber moulding manufacturers and can't find anything similar.