I agree with smiling monkey. You get the PPL in the country where you would like to fly. Or you can also get a certain PPL for flying that country registered aircraft.
I hope you do not think that a PPL is similar to an international driving license. It is not. That is why I have 5 licenses current. So that I can move around and fly aircraft in different countries without an instructor (Some schools require a company checkride, but that is a different topic).
There is also a difference between a validation and a conversion. as mentioned before. The minimum for a conversion is a few flights hours, airlaw and a check ride.
In Australia you can get a Special Pilots license. this is only paperwork; see
Civil Aviation Safety Authority - Converting foreign licences
But this is only good if you would like to fly VH-reg aircraft.
Honestly, It is hard to answer your question, because you are not clear with your question to why you need another PPL.