On the other side of the Tasman from you I've never seen Torx-15 one-piece drivers with the requisite 22-cm shank (or more) for sale in hardware shops. What you may be able to find is a loose Torx-15 bit (they exist) that fits onto a long shank with a hexagonal end designed for replaceable bits. You may be able to kludge something together with such a bit and a length of hexagonal rod. It may even be worth your while to prowl around eBay shops (for example) for one of the combined Torx-15 drivers with an attached 'case cracker' for Classic AIOs. Rots of ruck.

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