They are in Belconnen.
Thanks for the golf course at the Fairbairn! The place right before the boomgate at Mt Stromlo is fine. Just checked Google view - we should be able to park our cars there and see East and South sky reasonably well.
Grassy area on top of Parliament House is probably not a good option. Especially with setting up a telescope.
What about Mount Ainslie? From my memory there was some flat open space at the very top near car park.