Having read the post regarding importing goods from U.S. I thought about "ships stores in transit" but can't remeber the rules regarding this. Any offers?
I doubt that this is the complete answer but if the ship owner is VAT registered (in EC) then goods can be sent to the ship VAT free providing they are exported on the ship within a specified period of time. The seller has to inform HMC&E (or whatever they are called now) in his VAT return and provide the customer's VAT number.