Yes the "AU" stands for Australia, to differentiate it from Austria, which is "A". It doesn't seem to stop lots of Americans from complimenting me on how well I speak English when I'm up there however. No, I'm not kidding.
Incidentally, Hercus till exists in name only. They no longer have anything to do with lathe manufacturing and instead make gears and other poser transmission components. I have two Hercus lathes, and neither of them are especially great quality to be honest. Good honest machines that will last generations, but unfortunately they got caught in a no-mans land of not being in the category of uber-high quality and able to command a high price, while not being anywhere cheap enough to compete with the Chinese competition once it entered the market. With a bit of a tickle up however they can be made to be quite accurate, but will always be as rigid as a noodle compared to high quality toolroom lathes.