I dont' live in sydney but so it might be near the hills area, i drove from teh central coast to use these ppl, very very well priced:
Blackshaw "motor body repairs"
Seven hills NSW 2147 (it says hills in the name that must be a start)
96748655
I got my whole front bar done there, mesh taken off re fibre glassed week spots, bogged a bit that needed re shaping, then resprayed it and put the mesh back on, for $180 (and 2days)
They were also really nice to deal with, i highly reconmend them.