Yep, USPS is the way to go for a take-down, as long as the total price including shipping is under AU$1000. If it is more than that, I like to go with UPS, as they really offer great, fast service through customs.
For one-piece bows, the way I look at it is that we simply do not have access to all those beautiful old bows that you guys do, and we do live a long way from the USA, and so the extra US$90 (or even more) can be well worth-it and soon forgotten about as one enjoys a bow that can't be got any other way. That's how I look at it, anyway, and I'm sure some of my countrymen disagree.