Buy a Sonos Play:3 wireless speaker and get a free Sonos Bridge, 60 days music service and a 60 day money-back guarantee. (The page also mentions a 60 day music service trial but I'm unsure as to whether it will work in Australia or not).
Add both products to your cart and the cost of the Bridge will be discounted at checkout.
The price it gives me, including shipping, is £237.67 = A$389
As a comparison, Australian RRP prices are $419 for the Play:3 and $79 for the Bridge.
You will need to buy Australian power cords. These are readily available from electronics stores, although if you want white ones the only online supplier I found was here: http://www.alphaenergy.com.au/s.nl/sc.2/category.486/.f
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