I don't know if RRS has developed a plate for it yet but they are the ones I would wait for.
I made the mistake of using a generic that did work but it twisted and had awkward access to the pc terminal and cable release port.
I switched to the RRS version and could not be happier. It is rock solid, allows me to use my pc cords and cable release easily AND creates a strap attachment point that actually improves on Canon's (IMO).