There's probably not a huge market and I imagine greatest demand could be television stations followed by live theatre and film/television series production companies.
We've only got six main television channels/networks and probably not too many more film/tele production companies doing regular work.
You might get an idea on demand from employment sites like
SEEK - Australia's no. 1 jobs, employment, career and recruitment site and as to income I would not expect it to be much more than the average wage, maybe somewhere about $35,000 - 40,000 P.A