You may struggle to get someone to take you on in Sydney. Especially if you are only going to be around for 3 months. I found that due to the paperwork and supervision they are required to do, it is much easier for them to get someone who has full registration. I do know of one person who secured a job in a private clinic in Manly but she was doing that whilst studying to do the exams in order to stay in oz for longer.
Good luck!!