If you want a St Louis shipped to Dubai, you'll need to contact either the Paris or London stores and they will send it to you.
Depending on the laws in your country, you may need to pay customs duty before you can have the bag delivered. The good news is that the Paris and London stores will deduct VAT from your order.
There's a thread in the forum that has current prices for a lot of Goyard items. If you do a search, you'll see the cost of the St Louis. If memory serves me correctly, the GM is about 600 euros and the PM is about 150 less. If you mail the store of your choice, they will give you the exact price without tax.