A new Stern made for the US market will NOT work in any other country. You may find yourself having to purchase a new (Australian version) Main board - yes, it has to do with the 50/60 cycles, the MPU determines that the machine is in the wrong country and won't boot. At this time there is no easy fix for this.

Personally I think you are asking for trouble doing it. Is there any saving to be had? Importing is NOT a simple proceedure like sending a small package.

I wouldn't do it myself but you may have reasons - expect a lot of headaches though.