Lawful export of brass and projectiles for any reason from the US requires US paperwork. ITAR compliance is a big pain.
The short answer for the average Joe is - you don't want to go there...
Even a lot of US companies have given up shipping anything firearm related to other countries simply because they don't want to accidentally cross the bureaucratic Rubicon of ITAR regs.
Commercial companies who lawfully export such things typically don't want to deal in less than truckloads to keep the per-unit cost of the paperwork low.
(Paperwork is the same for 1 or 1000000 pieces of brass).
MtnCreek's link is a good place to start wandering thru the maze of bureaucracy you'll deal with.
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