It depends on the school. Generally GPA isn't too big of a concern for most schools so long as you meet their minimum. As for the MCAT, at a school like UQ that seems to be what they base your acceptance on at the moment, whereas a school like U syd has an interview on top of that. Finally I don't think they even use LORs/EC for internationals. Someone can correct me if I'm wrong.
No letters of reference, no cv, no essay. All they ask for are your marks and MCAT as an international student. I think the MCAT is weighted more heavily than your marks (just need to meet the cut off) with the interview playing a part. I would say the minimum MCAT is about a 30. Not sure about the writing sample score though.