Definitely a water dragon (Intellagama lesueurii) and you're probably right about it being a Gippsland Water Dragon (Intellagama lesueurrii howitii), as this subspecies has been recorded in the Kangaroo Valley and despite the skin not being particularly clean, there is no indication whatsoever of a dark stripe behind the eye, which I think would be visible if present, as the dorsal stripes can be seen.