Yes, Achim, it is easy. This has been discussed in previous posts. I've had it done as well.
Some years ago, when I began a search (after a judge told me my plating was zinc, not cad, thus incorrect...) I was told by a bunch of "experts" that you can't get cadmium plating done anymore in the USA, blah blah blah. (note: blah blah blah is American vernacular for useless talk)
Some went even as far as saying that because of EPA rules, etc. you can't get it done in California. Well, as they say, seek and ye shall find. I found two platers:
http://www.burbankplating.com/ and
http://www.prime-plating.com/ In an ironic kick to the "experts" you will notice that BOTH of these folks are IN California.
Prime did some Cadmium plating for me, for Tom Rose, and I believe for Bob Possel. As I recall Bob was not 100% satisfied because of the color; remember, the gold coloring is a phosphate wash done after the plating and many factors affect the resulting color. It is hard to maintain a consistent color from batch to batch. Most people are doing this for protection not color and thus the platers are not always in tune to your needs. I was quite happy with both the gold and silver cad done for me.
If you poke around other restoration sites for other cars, you will find other platers.
Impossible in Germany? A 2-minute google search for "Cadmium plating in Germany" came up with these guys: http://www.franzplating.de/Produkte/Cadmieren.html I don't speak German but it looks they they are metal finishing in Germany, and looks to me like "Cadmieren" is cadmium plating, and that's what the photo shows on that page...just because they do it in production does not mean that they'll do restoration parts. But, they probably know their competitors and can probably discuss your needs. They can't be the only ones, can they?
I'm sure if you make some calls you can find what you need closer than California. If that Franz plating is for real, sounds like experts told you the same stuff they told me...
I should add that
all plating processes include nasty toxic chemicals and "heavy metals". Cadmium plating simply adds the toxicity of the plating material as well. There are a lot of tin zinc, zinc, and other kinds of "home plating" processes available for you to do this at home. I would not do it; and hope none of my neighbors are either. I would not want to live next door to a meth lab and don't want to live next door to someone doing home plating either. An industrial facility has the ability to comply with national and local rules about the handling of toxic chemicals, materials and the waste. Home users faced with disposal issues simply throw the waste down the drain, in the woods, on the street...back in the days when I was in the printing business, I paid significantly as a "hazardous waste generator" (the waste was de-silvered photographic fixer) as a tax to the state, and also paid a firm to haul it all away. Ditto in the car wash business for sludge. There are proper ways to deal with toxic waste, and they just cost money.