I just thought I'd pass along information on topgearsuperstore.com a UK based gear shop. I just purchased a Shark S800R for delivery to the US (normally unavailable in the states but it was just too fitting to let that stop me).
TGSS was very quick to respond to my inquiries and even made changes to the website when my order initially had issues because of the delivery location. While the shipping isn't cheap, the time I have been told is pretty good considering. (about 1 week). I got quick information on sizing as well. All in all a very good experience so far. I will check back in once it hits my doorstep for a report on the helmet itself.