I have a few keys for sale :
$35 per key
EU/US
Stock : Sold out
Paypal only.
Regarding the delivery, I can input the key myself in your account using a remote control software such as teamviewer or I can give you the key via the skype chat, no refunds in the latter case for obvious reasons.
If you wish to buy please answer this thread specifying the delivery method you choose.
You need a battle.net account with Mist of Pandaria to use the key.