I've never understood why shipping to Australia is the same or more than to the US, unless it comes down to the degree of difficulty or the numbers that are being sold. I know to get a container from China is absolutely dirt cheap, but buying single items is very expensive once they are over a certain weight.
One thing you'll need to factor into your cost is the controller, you'll likely need to buy a new one that will work with the machine as the one supplied usually proves near impossible to get working properly.
So far as the machines go, they are all exactly the same, this email I recieved last week from a seller gives some insight as to who your dealing with on Ebay when you are comparing different sellers, chances are they are all the one company!
Don't be afraid to email the seller and ask if they can do better on the price, or on a "Best offer" offer a couple of hundred less, they'll counter offer the middle usually. You can generally save a hundred or so there at least.
Email recieved from seller:
"Hi, this is Alice, thanks for your time to see this email.
I'm Leaving the Taiyou trade Company which manage many eBay seller account, like love-happyshopping, rumei-shopping, Qiandingzhensatisfaction, tool-zoom, world-etrade, industry-village, wholesale2worldwide, equipmentwholesaler1, Hotitemsale, Happykisssoul, Digitalzoneproduct, Beautydirectmall and so on. "