David,
Unfortunately prices for any vehicle sold in the US that's available in other countries will always be cheaper by a significant margin. I'm considering importing a US vehcile when mine gives out and doing a complete referb of my UK model (or something to that effect). Prices in the UK vary from £9,000 to £12,000 which I think should be a good guide for Oz prices. Don't worry about a bit of soot on the tail pipe mine has that but just passed an emissions test and it's compression is still excellent.
The problem you have when looking to buy is there is much more opportunity for offroading in Oz so someone may have thrashed it to death. Tell tale signs are steerring joint play, suspension play or any scrape marks on the bash plates.
Mind you the stock Jap import is such a hard ride I can't imagine anyone doing anything severe off road.
Col