Are the sea shells legal to export from the US?
Are the sea shells legal to import to the receiving country?
Do you have all permits required for BOTH countries and any other coutries they may be passing through?
If you are talking about firearms and related parts, you need to remember that the US considers the receiver the legal firearm but, other countries consider different parts the legal firearm. Also, there are restrictions on exporting ANYTHING (bullets, primers, brass, barrels, etc.) for .50cal rifles from the US. There may be restrictions on exporting other "common" firearms parts from the US that I am unaware of.
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