I would definitely call them again and ask to talk to their manager.
Since it is their fault (isn't it? there is no rule that billing and posting addresses must be the same?), they should refund the loss.
I bought both of my sony readers from them and both times they where excellent.
P.S.
I have come across this inconvenience of ordering from abroad, then cancelling the order myself. You have to pay the charge twice to your credit card company
