Hi James,
If you are not keen to try the military route then Gapan is a good place to start, although I think the only rotary scholarship they offer currently is for an instructor rating which requires previous qualifications.
As you are under 23 it would be well worth looking into the Dennis Kenyon Junior Helicopter Flying Scholarship. It was set up by Dennis in memory of his son, further info here:
Griffin Helicopters | Dennis Kenyon Jr Scholarship
It offers a great opportunity to do your PPL(H) and would also give you a really good introduction to the helicopter industry!
Good luck with everything,
Nobby