If you are going to the Gold Coast (ie Bigger Waters), you would want to get further north than Coonamble.
Here are your options:
Mildura to Dubbo (8 hours)
Dubbo to Lightning Ridge via Coonamble (4 hours)
Lightning Ridge to Gold Coast (8 hours)
Or
Mildura to Dubbo (8 hours)
Dubbo to Moree via Coonabarabran (4 hours)
Moree to Gold Coast (6 hours)
I would stay at Moree’s Gwydir Caravan Park & Thermal Pools – take your swimmers and relax in the artesian baths after the long drive. They have a Deluxe Cabin with 1 double, and 2 single bunk beds for $79 – you would need to take your own linen. If you would like to book, please phone 02 6752 2723.