Vanbar in Melbourne (http://www.vanbar.com.au/main.html) and in Sydney have the ingredients, but you would need to phone them first to ensure that all the chemicals are in stock. Their web site is a bit of a mess, and the old address of the catalogue might be better:
They have a number of kits for developers, but not PMK. They might make up exact quantities for you to facilitate mixing if you don't have a weighing scale with you. Ask for Mario at the South Yarra store (Wednesdays and Fridays, I think) on +61 3 98.27.08.77
If all else fails, and you are in melbourne, you could weigh the chemicals and mix them at my place. In other cities, you could probably find APUGers that would do likewise.
If all else fails, try mixing your own. I made up a batch for this year's work and it turned out fine. I never thought I would be doing this, but it was very easy and much cheaper once you have the scales and raw chemicals. There is really very little you need to know in order to do this type of combination. Some distilled water, a couple of beakers, chemicals and a scale are all it takes.
I know you can buy from Artcraft or Photographer's Formulary in the U.S. but I don't know about shipping to OZ. You might try them with an email and see where you end up. They are both knowledgeable and decent to deal with. If you decide to do it this way, remember that PMK keeps well, so order enough to see you through for a while. Remember to use distilled water for your working solution, as water quality varies considerably and times will as well if you don't use distilled. Best of luck.
Vanbar in Melbourne is the only place that I know of. The South Yarra store seems to specialize in stocking chemical components whilst the Carlton store has much less of this sort of stuff. You can get the components for PMK and also for Pyrocat-HD ( Much better for VC prints IMHO ) from this shop.