The white V on the face seems to be specific to Anthelidae, and Epicoma species in Notodontidae, but it does not look like any of the 22 caterpillars illustrated at http://lepidoptera.butterflyhouse.com.au/anth/anth-cats.html or the 7 species of Epicoma in http://lepidoptera.butterflyhouse.com.au/noto/thau-cats.html
I think it is too big and too hairy for Epicoma, so it is probably one of the other 52 named Australian species in Anthelidae.