This auction turned out nicely. The seller was obviously not a Rick-connaiseur, but he seemed honest. He listed the auction with this picture:
The rest of the pictures in the rather confusing listing wasn't too good either:
I took a chance and it turned out great. The seller was a nice guy in Berlin. We exchanged friendly e-mails, and a week after the closing I had the bass in my living room! Goes to show that good deals still exist even on ebay. (The price (1570 euros) was very reasonable, remember this is Europe!)