Old German bicycles are rare in the USA. On a macro scale, they are rare even in Germany.

I was in Germany a couple of months ago and, naturally, spent plenty of time eyeing up the bicycles in use there. Most of the commuters and functional 'fahrads' as they are called in Germany were heavy (sturdy), upright working machines. They were strong looking, but not what I would call handsome machines. Most had internal hubs. Some were five and seven speed internal hubs which I thought was particularly functional and appropriate for getting banged around at train stations and shopping center bike stands.

I did see one reproduction of what looked like a USA fat-tire bike from 1930-1950's. Like I said, it was a modern reproduction. This one had a WWI Kaiser cross on the tank and had tires that made it look like a German war motorcycle. Kinda cool, but not as cool as some of the custom jobs I have seen in the States.