Cheapest I could find in Perth was Reece Plumbing. $9.00 per metre for 1/2 inch, Bunnings were asking $12.00, Galvins wanted $17.00. Talked to a scrap metal merchant at TWOC, he reckons he was getting $6.00 per metre, so I guess it's just expensive now. Ended up getting 10 metres from Reece.
Cheers