Blizzard has opened paid transfers from PVE to PVP realms.
"Providing a smooth and enjoyable experience for all players is always a priority for us, and we are continually re-evaluating our policies and programs to do so. As the state of the game has matured substantially since the inception of Paid Character Transfers, we will now be allowing PvE-to-PvP transfers on a full-time basis to provide players with more mobility and freedom to easily play with their friends.More information is available here.
Keep in mind that all of the other standard cooldowns and restrictions will continue to apply; we're just opening the option to transfer characters on Normal realms to Player-vs.-Player realms. Please review the Paid Character Transfer FAQ if you have any questions on how this service works."