In Boston (Chestnut Hill actually) the men's Bloomingdale's carry them. My guess is the NJ and NY stores would have them as well. I emailed Belstaff a month ago re: one of their bags, asking them where I could find it (Bloomingdale's only has jackets) and never heard a word from them. Nice customer service.
GQ has been flogging Belstaff pretty hard lately. You can check in there "where to find it" in one of the back issues if you don't get an answer here.