Hey Michael,
The Austrian Kappe has become a rather spendy item in the past few years, and because of that, there are a lot of reproductions out there. Many were made for reenactors, but some were made to decieve the buyer. Many of the Kappes that end up on Ebay.de could be real, but it is really hard to tell with out handleing them. They sho up at SOS sometimes (I picked one up last year) and that may be a good place to pick one up, but the Euro has made the dollar prices a bit high, running in the 400Euro range, and that gets the dollar price up around $600. The Emperor's Coat is a very good refferance to use, and if you wish, I will bring Joe's copy (I borrowed it a few years ago, and never returned it).
Best wishes
Gus