Skipper, another source in Europe is Black Lion Decals in the Netherlands. They do custom work, and I've been VERY satisfied with what they do.
I needed some specific "bumper numbers" as well as other misc. decals to complete a 1/35th scale 5-ton truck I did recently. I told them what I needed, the sizes, etc, provided a picture sample of the font of the letters, and they did the rest. They sent me a PDF proof sheet ahead of time to verify that what they were getting ready to make was what I wanted.
If you've got a picture of what you want, I'm sure they can handle it!
Here's there website, and while you're there you can check out their gallery to see what they've done. I sent them photos of my 5-ton which are in there.
http://www.blackliondecals.nl/index.htm