When I was stationed in Germany during the early 1980's I had a poster that I had bought in a German department store.
It was pretty cool and I wouldn't mind having another one framed.
I found an old photo that has it in it and thought that maybe one of the members in Germany might recognize it.
It's in the upper left corner of the photo on the wall.

Here is a close up but the image quality is very poor.
It is a painting of a girl standing beside a horse and the horse's mane blends in with the girls hair so well that they appear to be one.