need nyo talaga ng nbi clearance. there is no going around it. the good thing is nasa ACT kayo. very convenient to go to the embassy and apply for one. may i suggest na i-upload nyo na din yung scanned receipts nyong dalawa kasi it's going to take awhile to get them. lalampas kayo malamang ng 28 days.
https://immi.homeaffairs.gov.au/help-support/meeting-our-requirements/character
Police certificates
We may ask you to provide a police certificate (also called a penal clearance certificate) from every country you lived in. If we ask you for one, it will usually be if you are over 17 and lived in any of the listed countries, including Australia, for at least 12 months in the past 10 years.
Police certificates are valid for 12 months from the issue date. They must cover:
_the time you turned 16 up to the issue date
or
the whole time you were in the country_