Dan, nice find in Oz, but don't think you'll need a manual as it looks very simple inside. Just a small amp with two valves that should be rebuilt. And the two motors should be pulled down and serviced too. Even if they work I always pull them down and have found so many issues that way. Just about always the grease has either turned to gunk, dried up or gone. Lots of dirty crap inside on every surface which can cause seizing. And the motor wiring will likely be disintegrating due to oil and heat damage which can be as simple as sliding insulating covering over or probably replacing.