I bought some from Franzose about 3 years ago, but they're not a very good fit. I had to cut the rubber at the base to stretch it to fit. I had the same problem with their number plate light rubber - too small. I had to cut that in a couple of places to make it fit. Sent them an email complaining but never heard back. You could try cutting your own. I made one for the boot handle out of rubber sheet about 2mm thick which turned out pretty well.
I agree with Dano ........It is often easier, cheaper,and quicker to cut your own. Clark Rubber, for example, have an excellent range of rubber sheeting and I have cut quite a few seals and gaskets etc for my 203 restoration project and none of it was a hassle. A quality craft scalpel with changeable blades, plus a steady hand is all you need! No problems with international refunds either.