Now, if you're like me and are Australian and also happen to live in a regional area then you may find it difficult to find the paint of choice for most of the community: Krylon Fusion for Plastic. It seems that it's the go-to paint for the American enthusiast and as such you run into flat recommendations of "Wal-Mart carries it", which doesn't really help you.
So after some searching I discovered that Crockers Paint stocks it and that they take online orders! I just bought a couple cans of the Flat Black for $12.95 a can and it cost me around $18.80 in shipping, which is a small price to pay when you have no other options xD
As soon as I get them into my hot little hands two of my work-in-progress tanks will have nice and black backs which will let me get on with the rest of setting them up.