I don't know of anyone in Brisbane, But maybe a call to DBA, Race Brakes, Pagid (Barry Smith Motorsport), or AP Racing may give you a lead on custom hats in Brisbane. I had mine done through Harrop in Melbourne. They are usually machined up from aluminium. Make sure you've calculated your offset correctly. On your other thread you mention rotar thickness, Any good brake shop can mill down new pads by 1mm very cheaply. Might save you a bit of hassle.