What is your situation?
If you are new to floats then my advice is to get your ticket on a piston machine and gain ICUS, but if you are caravan specific or have to get checked out due employment then either go for a place that has them on floats already.
As mentioned Sydney do training but are expensive, however sxf is a nice machine. Air Whitsunday do float training and fairly sure that covers caravan training too. Machines are not as nice but it is one very nice part of the world to train in!