OC is reasonably popular among people who are into opiates and stuff but it can be quite hard to come by. Doctors in Australia are definately nowhere near as forth coming with painkillers as they are in the US but atleast we have OTC codeine I suppose.
You get oxycontin in Australia, as well as endone (5mg IR) and oxynorm (10mg) but it isn't easy to get scripted. I don't know why there would be a huge difference in the popularity of OC between east and west, I suppose I can see how the larger heroin scene on the east would make opiates in general slightly more popular.