There's a Brissie based shop that sells really good quality stuff, and they give bulk discounts. If you go in with a few others you can do heaps of colours.

I have a dyeing platform* at my house, and thre laundry sinks, so pretty well set up. I am planning a dye day pretty soon. I'll invite you. I'm dyeing onesies, muslins, some plain old jersey, shorts and singlets.

*Platform = giant concrete shelf at waist height. Not specifically designed for dyeing, but it was the first thing I thought of when we bought it!