I think you are misunderstanding. The customs office says they want a receipt so they can charge me the tax. If I don't send them the receipt, or in this case my girlfriend, they'll just return it to the sender.
I can mail you a copy of the letter we got from the customs office. It's in portuguese, not sure if it will be of much use to you.
We can wait for this carton to go back to you and for you to reship it as we're waiting for another order already.