Hi Raglan86
If you only have a three year degree getting registration in NZ is quite difficult. As a back way of getting into Australia I don't think you would find it is very easy, particularly with your lack of experience. Our degrees are four year degrees, as in Australia, so when you apply that is the yardstick that you are being compared against.
Have you considered doing a year to upgrade you qualification in Scotland or Ireland? for example here is one at QME where you can do a Msc - 1 year part time or 2 years part time.
Physiotherapy Courses at QMU Edinburgh
I know it is more time and money but you working for no money anyway and at the end of it you would have a much more robust qualification that you can use for entry overseas.