Firstly, forget buying N1 motors. They are utterly pointless and a waste of money as they still carry all the weaknesses of the RB26.
You can have a motor built for less than a N1 costs, and it will be unquestionably more reliable.
The list of parts for that power output (320rwkw), is nothing more than expensive.
You do not need:
Rods
Stroker kits
Nismo Plenum
HKS piping kit
Upgraded intercooler
Manifolds
Everything else you have parts wise is good. The above will save you at least 5k which realistically, you'll never notice on the street and won't affect reliability at all.
My own GTR makes 350rwkw with pretty much everything factory... Plenum/dumps/cams/crank/cooler/piping/rods/manifolds etc.
Just a rebuild motor with forged pistons, new crank, head tidy up and some strengthening of the block and there isn't much more too it than that.
As you are in WA, go down to XSPEED or similar and have a chat with them down there. No point going to the East Coast when you have a perfectly capable workshops over there that won't make you eat your money freighting stuff all over the place.
How the mining industry affects car mechanical labour, i don't understand. Good work costs good money.