I’m surprised it hasn’t been floated yet - but my recommendation would be Jeremy Miller (UPRT Australia) at Archerfield.
I use him for peer review & as my coach at the AULT level - a bit of a passionate hobby of mine.
Great ability to teach, awesome / balanced / humble personality & he has a Decathlon, Pitts S2 & L300 Extra available.
I would not recommend initial TWU in a Pitts - suggest Decathlon to start, but no reason why after the initial a transition to Pitts couldn’t happen with a good mentor. Just makes the learning more “graduated” & less frustrating (for front & rear pilots!)