I don't know what aircraft are fighting fires at the moment though if I was the government
I would buy the Beriev BE-200 say get 10 of them. Attached them to the RAAF for training
and logistics. They can scoop 12000L on a touch & go they would put out the front line of a fire storm
quicker than that 737. They can configured to search & rescue, maritime patrol, cargo, transport up to 72 pax.
I think it's an ideal aircraft. Just a suggestion.