Thanks for the replies.
I am currently living out in western NSW, but planning on moving to Vic later in the year.
An MC21 would be the preferred option as it is much easier to derestrict - no messing about with PGM cards. I am aware of the differences between the models (adjustable suspension, magteks etc), but noticed some comments regarding HRC gearbox parts being suitable for SP engines only. That is the basis for my query.
I had planned on replacing the front end (NC35 or preferably RS250), and getting an aftermarket rear shock. I have also found a number of dealers in Aus that can supply parts - so no problems there (except crank bearings eh?).
After my experience with the NS400, I would be looking at having a complete spare engine as well as building up a stock of numerous other spares, to keep the bike as a viable long term option as a road bike.