im in sydney so cant help on locations...
but i blew my clutch on monday, im looking at either an os giken or might call Jim Berry. i think he's up in qld. theres a couple of threads on his mad clutches, just search around.
as for your flywheel, you might need to get your existing one machined anyway, if you blew your clutch badly enough you might have torn chunks and put scratches into it.
money wise - maybe around $300 for just a replacement nissan stocker up to around 2 grand for a crazy circuit/drag application. theres a mariad of clutches in between, up to you to decide how much you wanna spend opposed to what quality you want.