....I think you are missing something.
OSIR and TT Shop have a strict agreement between them whereby TT Shop is the exclusive reseller of OSIR products not just in the UK but Europe.
A lot will be down to the American OSIR reseller as to how things are done but they will be under a similar agreement.
Unless you are a holder of a very large Diplomatic Immunity bag, good luck with customs on both sides of the pond!
Just because there's a commercial agreement between two parts that one is the exclusive distributor of another party's (the original manufacturer) products doesn't stop me from importing the product myself and selling it myself. If I'm doing enough trade that the distributor wants to complain they can lodge a civil complaint but that's about it really, as long as there's no agreement between me and the original manufacturer (which would violate the exclusivity between the original manufacturer and the distributor).
Likewise, the distributor must still pay tax on that which they import but they will be able to recoup the tax. There shouldn't be any customs fee to export a product either.