Flux Capacitor Wires
The closest I've found so far are the Accel 3009 7mm Super Stock wires. While these will fit the bill for now, they are not an exact match. The orange boot is not as round at the 90 deg. elbow as the originals appear to be. I will keep on looking and report back if I find better. These are available from the Amazon link at the right. The good part is that you get 8 wires, good enough for two Flux Capacitors with a few extras in case you make a mistake cutting them to length.. Just cut them 2-3 inches longer than you need them to start with as the extra will be below the panel.