Du to the fact that there are strict gambling rules in your country and this is a public forum - nobody will tell you (openly) were to play using bitcoin from your location. If I was you I would ask privately to some of the Australian members here or on other gambling-related forums (preferably Australian ones).
I know how it works in one of the other countries where online gambling is totally banned so I am pretty sure that there are Curacao casinos that are focused on Australians too. Yes, they are operating illegally in your country but they are trusted among players.
Their web address constantly changes but they keep you informed via email about their new one (mirror address). This is made to keep them running in case your government somehow finds them and blocks their domain. Their live chat, as a rule, will be able to give you a detailed explanation about what details to fill in your registration fields.
As you going to use bitcoin, your name and address can be anything - the important is your email, because you may need it in case you forget your password.
Remember, do proper research and do not trust much to information that is on affiliate sites offering you to play here and there! Try to find the info by real players. In case you find the casino - make sure to ask their Live support all the questions that might worry you in future.
P.S. Regarding VPN, I would make sure a VPN service provider is not located in your country.