I am interested in this too. I don't have a bike yet (Will get one as soon as I get my bonus), but since I have been thinking about getting a XB12SCG for a year, I already know what parts I want. Anywho, I think someone got a set from PM-Performance in Switzerland or some place. http://www.pm-performance.ch/seiten/index.php
Can anyone translate this and let us know what all is included? I am assuming the seat is unique also as the angle of the subframe is changed slightly. Also it is a little longer due to the spacer. It does look nice though[up] Here is a pic of another bike I found with it on it. I especially like the gas mask headlights.
I just looked at PM's site again, it says something about the original seat. I have learned a few words from looking at the foreign sites. Sitzbank or something means seat.