Unless you do not care about quality, do not buy from China even if it is allowed which it probably isn't. The Virginia Tech killer bought some of his equipment on ebay. That is why they have such tight restrictions here. You can't get around the restrictions by buying from another country.
According to the policy, the seller and item must be in the US.
http://pages.ebay.com/help/policies/firearms-weapons-knives.html
Perhaps you can find a local gun dealer who might be able to point you to someone who sells what you're looking for if they themselves do not have it.
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Non payers should get unpaid item strikes and be added to block bidders lists. Period.