I also know of a supplier of perch, yabbies and catfish etc up near port macquarie who is well connected in the Aquaculture industry and he may be able to help you source trout fingerlings, or if he can't may at least be able to recommend someone.
PM me if you want his contact details as I'm not sure if he'd like me posting them on a public forum
Perhaps this DPI trout hatchery would be worth contacting also? "...the department’s fish stocking program... is recognised for its importance to the community in terms of quality recreational fishing,
stock for the aquaculture industry... etc etc":
http://www.dpi.nsw.gov.au/fisheries/info/gadenIf I were you I'd contact DPI and ask for recommendations - they've helped me in the past track down certain fish suppliers close to me.
hope this helps..