GSP is only available to sellers located in the USA or sellers located in the UK.
The Seller ships to the GSP center in their country. Then the item is processed and sent to the destination with all taxes, duty and other fees prepaid. eBay sometimes rolls all the costs into one "shipping" number when displaying.
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General rule of thumb, when you see two different costs, assume the higher one is what you will get hit with as a Buyer.
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