Have you consider the Remote Audio Multipair cable? It's a 3 channels (3 pairs) cable. It's sold by the foot. The channels are readily made for that purpose, color coded (blue, red and black for the stereo return), you just wrap them with techflex after the fan out and there you go. Used Neutricon 8 pins for the breakout part. Cost me about 100$ for a 23' snake.