DO NOT mark gift on the package. That is illegal and unethical.
I would not ship it overseas, something that costly. if she really wants it, she can deal with an import/export agency in the US. You mail it to them, they send it to her.
Sellers have few enough protections on ebay and selling internationally just makes it worse. I have been selling on ebay since 99, I have about given up on international selling. Too many headaches.