We are have problems for the moment with finding a supplier in Europe who has a RGB LED matrix. It's surprisingly hard to find. We prefer to use the COM-00683 RGB LED matrix.
We are hoping to find an 8x8 RGB LED matrix and otherwise we will have to make it by ourselves with 64 separate RGB LED's. I also drew a schematic of the circuit we are going to use, you can see this here: A close up of the LED matrix: