OP: Your UON degree is from PSB or in-campus from Australia?

If latter you can try applying for engineer positions in those mncs and emphasize in your cv and make sure they don't mistake it for the PSB one which is very common among private graduates in Sg.

If former, my advise will be to focus on the smaller companies who are not directly doing aerospace engineering, but provide services to aerospace industry along the value chain. Don't restrict yourself just to engineer jobs, broaden the search to sales, procurement, safety, trainer, project support etc. Go for areas less popular = less competition and since your expectation is 2.5k should have a good chance.