Personally I suggest you complete your physiotherapy degree In North America - The reason being getting registered to work in Australia / NZ and other parts of the world is far easier with a North American Doctorate of Physical Therapy... while going from a bachelors degree (found in Australia, NZ and England (honors) ) into a country that has a doctorate programme is far more difficult. The other aspect to consider is that international fee's can be excessive.
You have to decide what is right for you and consider how difficult it will be for you to re-register in your homeland with a foreign degree.