Atlantia, I posted the pictures of the Rapier in the European Armoury forum hoping to get more information on it than I have now, which is little to none. If you wouldn't mind please take a look at it there and if you would like I can even post close-ups of the 'mounting system'.
Thank you for your interest and thanks to all the others for sharing their ideas and wonderful displays with the rest of us in this great thread.
Robert