407 - IMHO, the best non military single engine ship around as far as power, speed and smoothness. However there are less than 10 copies in Aus, I am told, so support may be a problem? Also glass cockpit won't like your 40+ summer days Down Under. 2 back facing seats and 2 cabin compartments is a disadvantage for sightseeing. Be prepared to send your 407 to the mechanics regularly.
B2/B3 - Great power, close to but not as powerful as 407. Hydraulics are a concern though. Better passenger layout than 407. Also you'd have to deal with the French - although they are getting better and timelier with spares. Far more copies of B2 and B3's around than 407 so the backup expertise is very good.
EC-130 - Very beautiful lines, very modern and very expensive to run. Terrible range but you can put in an aux tank. Up to 8 POB all facing forwards. Only a handful in your part of the world so servicing/spares/expertise will be an issue. Flies almost as beautifully as the 407 in terms of speed, grunt and smoothness.
206L-IV - Old, venerable, very reliable, cheap but a very good ship. They're everywhere so there are almost no bugs in them, spares are cheap and you can buy them at any Walmart (almost). This is a Holden (in Australian parlance) instead of a prestige model like a Cadillac.
Don't worry about left and right foot pedal use - like driving a LH drive car in the US or a RH drive car in the UK, you'd get used to it.