The bush flying jobs in Oz just need a bare CPL. Ideally you should have a Night VFR rating. You don't need an IR but they never hurt.
The company I worked for had some float planes. You do one season on the wheels and if you want, next season you can go onto the floats. You start on the closed water and eventually work up to open water.
Oh, there's a big shortage of pilots in Oz now for the regionals etc.