Just ensure Left Hand Drive headlights dip the correct way for an Aussie (Right Hand Drive) car.
Some vehicles uuse the same light assemblies and you switch from left ot right with a lever on the back of the lamp.
Clesior lights should be common here.
Try a PM to "siddley" in the UK.
He's parting an LS400 and it will be right hand drive. Their postage isn't cheap but the parts most likely would be.