I noticed at least 2 free camp sites recently both in the Pretty Valley area which is about 6-8 km out of the township turning right towards Mt Mackay.
The Pretty Valley pondage is a nice little area and suitable area off the road along the way.
It's probably worth driving all the way and then turning round to go back to the place you like best.
On the same rd/general area is Mt Mackay - a smallish hillock with Tower on . There was a very pretty area about 3/4 to the top - say a km from the bottom with a fantastic view looking towards Hotham way. Would be a great day /overnight or 2-3 day stopover.
Falls even in summer has a cafe and small supermarket plus pub open. No fuel though.