While I didn't quite redeem so many Avios (I think I redeemed 130,000 this year, but three were MFUs), I redeemed around 400,000 Qantas points this year as well. The availability using Qantas points is basically the same as reward flights with Avios, so it definitely can be done.

One thing that is a bit difficult is the OP's timing, I suspect. 6-8 weeks out may well be the worst time period before the flight to try.

I second KVS tool and Qantas website (which brings up some alternative, somewhat convoluted routes as well, which may prove useful to the OP), and also there is AwardNexus, Expert Flyer etc that the OP could try in order to simplify things.

While using the QF website, the OP needs to remember not to think that QF points / Avios rates are the same, though - there is often a huge difference. So, I recommend using the QF website for availability search only and take no notice of the points required.

Also, it's worth splitting up segments, trying odd routings (which I admit I have had to do, e.g. SIN-SYD via HKG).