I'm not sure if these folks are still around but I got my bag here. If not there are places in the UK where you might be able to get them from.
The US dealer is:
CIMA INTERNATIONAL
399 Wall Street
GLENDALE HEIGHTS, IL 60139
Phone 630.671.9710
Fax 630.671.9701
E-mail helmets@aol.com
Took about 3 weeks to get it.
I have the tank cover with the tank bag so if you have any questions about it let me know. I'm not selling mine. I use it and like it.