I got the bellhousing sent over from New Zealand, I wouldnt try locating it in Australia. I took it to a shop, they did the conversion, I know that the bellhousing had to be machined to fit the ka internals, but at the end of the day it was well worth it.
And if i chew through a box, all I need to do is replace the internals with KA internals and away I go. Also means standard driveshafts etc.
I would be interested to see how he has done the bracket for the clutch.
Also using the 50's series box, means you can use an sr20 awd flywheel and larger clutch, which believe me makes a massive difference.