There is no Qantas Club as such although you can us the AA Admirals Club if traveling with AA that day, if you have one world elite status there are a number of options:
Admirals Club
Location details: Terminal 2A, after Passport Control to the round satellite by Gate A37-39, taking the escalator down.
Opening hours: Daily 07:30-22:30
.
Cathay Pacific First and Business Class Lounge
Location details: Terminal 2A, Mezzanine level
Opening hours: Daily 10:00-1400; 15:00-19:00
Notes: Access to First Class Lounges is restricted to Emerald members or those travelling in First Class
.
Salon l'Espace*
Location details: Finnair: Terminal 2D
Opening hours: Daily 05:30-last departure
Operated by a third party on behalf of: Finnair
.
Air France L'ESPACE
Location details: Terminal 2E, Level 1 after immigration
Opening hours: Daily 05:30- 24:00
Operated by a third party on behalf of: Japan Airlines
* At peak periods, access to certain lounges may be restricted due to capacity constraints. Access is available on the day of departure when the next onward flight is with a oneworld member airline. Access may not apply at a limited number of third party lounges.
If you used Orly with BA you would have the BA lounge to use:
Terraces
Location details: Airside
Opening hours: Daily 05:30-22:30