Thank you for the response. I'd like to add some more info incase somebody else has this question in future.
"Yes you can, but expect to pay import. There are companies who let you ship to their warehouses and they will ship the product to you for a small fee, that's probably the best way, but it's going to end up costing just as much so it's only useful for NA-unique products.
Also, some companies ship worldwide, such as NCIX.com/.ca just started doing a while back."
"I've done it to Mexico by plane, but as ----- says, there is always the risk that you will get stopped by customs and have to pay duty.
This haven't happened to me yet."
(referring to foriegn cards) "Amazon will take them as long they ship inside the US. (at least for hardware) and of course, that you're card is Mastercard or VISA (not sure about others), is a different history while buying codes for games"
"Newegg should work too, not sure about Microcenter (Bought a processor there but in-store)"
"If you built a small form factor you could take it home assembled in your carry on. You usually have the right to travel with your computer, so you just say that you traveled with it and came back with it for work or something."
"If you get a small and cheap case would be great, you can get rid of it after you arrive back (and avoiding paying duties).
I used a Santander card with Mastercard. Did both but they deliver to hotel, just notify the hotel to receive it (and if it arrives before you arrive at the hotel be sure of having a reservation)."