Pistons can be organized VERY quickly.
Ring up Quantum Racing in Brisbane, they're the CP importers, give them the specs and tell them its a rush order and you need them as fast as humanly possible.
With custom pistons they can be done very quickly, the price goes up by a percentage based on how rushed they are. With JE from memory its 50% surcharge for a 48hour turnaround, then express air mail which takes about a week door to door.
Expect to spend more than $900, but you will get them done in time.