Wirelessly posted (BlackBerry: BlackBerry8530/5.0.0.601 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)
"They're not that far off: As I see it, LAX-SYD-LAX in PE would be 150,000 miles per person, and they'll hvae 275,000 so it's not that much of a shortfall to try to make up by one means or another."
Well, yes but ...
The OP is not starting from LAX, and is not ending in SYD. By the time you add the BA surcharges for flying on QF, the cost of two YVR/SEA-LAX roundtrips and the cost of two SYD-AKL roundtrips, things will start to get expensive.
The OP might (or might not) prefer to fly Coach, and stopover for a couple of days in HNL. It will certainly cost less, even with the hotel room.