I bought this helmet from Weitze while I visited his shop in Homburg in Dec 2007. Helmut told me that he had gotten the helmet from a family (the owner's family???) and that to the best of his knowledge it was authentic.
There were only four officers who wore this style helmet, and for less than 10 years. I didn't know of any other unit that took a silver eagle with the Fuerst banner, so I thought it was probably an issue of expedience to get a silver plate. A friend and fellow collector in Tennesee has one of these helmets also, only his has the Fuerst banner. After I had owned this helmet for a few years, and went through many of the thoughts and observations that you all have posted in this thread, I decided to return the helmet to Helmut. There were no questions asked and he graciously took the helmet back without any problems. Helmut Weitze is a class act and an ethical businessman, but as with any of these items we have a responsibility to know what we're doing and use all of our knowledge and skill when we acquire something.
I've asked Joe to post some photos that I took of the back side of this plate. There is no question that this is a Koenig plate.
Jim Turinetti