Unfortunately, they seem to be almost entirely a North American thing. (Disclaimer: I haven't looked in more than a year, but I could nothing in Australia, let alone near Sydney. The closest I found was actually quite different.) SCAs are similarly hard to find, but I know they exist here because I've met people who participate and there are certain Aussie TV personalities who routinely take part. I suspect our relatively low population density has something to do with it...
That said, we city folks do have blacksmiths come show off their trade at various shows and festivals throughout the year. They *always* draw a crowd. Most of their employment is horse-shoes, but some do work with steam engines.
Wade.