https://www.casa.gov.au/sites/g/files/net351/f/_assets/main/lib100191/rr61_medical_fs.pdf
you can fly a PPL with a RAMPC - there are limits to what you can do with it though - generally 1 PAX, SE max 1500Kg, DayVFR, under 10,000ft. One thing you can't do is a PPL Flight test without a class 1 or 2 medical. (whoops, another stuffup with Part61). If you have a safety pilot with a class 1 or 2 you can do more.