I'm not familiar with the temperatures down under this time of year, but if it doesn't freeze, it should be OK. They are actually frost tolerant and a bit freeze tolerant, at least the above ground parts.
Here in the US, people generally plant them in the spring, the "best" time. If they plant it in late summer, they don't expect a harvest but it will grow the root/rhizome system. The longer the growing period, the better it will do the next season.
In your case, don't expect much out of it until the days get longer, like in the springtime. If it does anything, even a little growth, that's good for the underground part of the hop plant.
That would be a good topic for Grow-Hops. There must be some other Australian hop growers on the list out of the 3K members.
http://groups.yahoo.com/group/Grow-Hops/
If you think you might have a problem with your weather, you could put it in a large pot and grow it indoors with artificial light.
As for the lighting, at least with aquarium plants, it appears that the cheap florescent bulbs (around 3,500 to 4,000 Kelvin) do better than the Grow-Lux bulbs or the 10,000 Kelvin bulbs.
Hopefully, your hop will do fine. Generally, they do better in the ground than in pots, and if they are in pots, pots in the ground should do better than above ground since they will keep watered better.
If you decide you want to grow hops, save your money and get smaller rhizomes from a commercial source other than eBay. You got a really healthy looking rhizome that will probably do very well much faster than a small one, and these DO cost considerably more than small ones, but in the US at least, we can get rhizomes for less than USD $6.00. Some sources are in our links section of Grow-Hops:
http://groups.yahoo.com/group/Grow-Hops/li...s_001197133665/
You may need to join to see the links, but here's two:
http://brewerschoice.net.au/html/contact%20us.htm
http://www.grainandgrape.com.au/articles_o...prhizomes01.htm
According to the last link, the time for buying hop rhizomes is in July, so you're only a little bit early. GrainandGrape have these varieties:
Chinook, Pride of Ringwood, Cluster, Goldings, Hallertau, Hersbrucker, Mount Hood, Nugget, Perle, Precoce dBourgogne, Tettnang, Willamette, Wuerttemberger
I have never heard of Wuerttemberger and Precoce dBourgogne, but you have some varieties in Australia that we don't have here. Same for Pride of Ringwood except aht I have heard of that one.