RDZ (the original one) and BPX were sister ships with consecutive serial numbers off the production line if memory serves me correctly. I believe the original RDZ now resides in the graveyard at Charters Towers airport somewhere nearby Dennis Behan’s hangerage. Both were C402 ‘straight’ models. Air Mt Isa operated both for many years.
https://www.airhistory.net/registration/VH-BPX