Probably not something you can just run down to Jaycar and get anymore... you'd honestly probably be better replacing the switches to a newer flip style. It won't look anything like what you had, but at least get you into a usable stateand get you up and running, you could just wire in a couple ST0570 from Jaycar.
Let's be realistic, they stopped making them in the 80s right? You could try asking in the American section of the forum to see if anyone over in the states has a dead unit they can pillage parts off for you, but I dunno if you'll have much luck.