At the moment Mt Stromlo are not running any public viewing nights due to a number of reasons. However the visitor's centre and cafe

are open during the day and visitors are able to take self guided walks around the observatory grounds.
The Canberra Astronomical Society operate a Meade 14" on the site for the use of members and guests, however there are no pre-scheduled sessions and members arrange as required.
Normally the "Canberra Space Dome and Observatory" in Downer offer a pay-to-view facility with impressive scopes operated largely by CAS members. Unfortunately, I've just been informed that they're shut for maintenance through February

...but it could be worth a call just in case!