I'm assuming that RCSI Bahrain awards degrees equivalent to a degree from RCSI Dublin? If so I believe you will be able to intern in Australia. In final med (NUI, Galway) I enquired about this and found it can and does happen. As an IMG, you will be restricted to intern posts they are unable to fill with graduates of Aussie universities. That pretty much rules out Sydney and Melbourne, but there usually are vacancies in and around Perth. I ended up interning in Galway though.