Not sure about australian uni's that offer these subjects but several states have Welcome Back Centre that help overseas trained nurses fill in the gaps. I think there is a specific course in California, I was lucky enough to find a college happy to take me on for two subjects which is very rare but may be changing. Deaken uni in australia looked to have a single maternity unit. The thing is I lost a year trying to sort this out and the actual clinical hours for Maternity and Peads was very minimal compared to the weeks of clinicals us Aussie's do.