Thanks Frigate Bird and Harley D. Not too many historians amongst DG&P Pruners it seems.
I followed up on the Airtourer possibilty. Turns out that a well known New Zealand ferry pilot, Cliff Tait, flew an AESL Airtourer (Oz design but Kiwi manufacture) most of the way around but shipped it from Japan to USA. Nearly but not quite. Looks like the Bendigo boy's claim is genuine.
I see that this morning they got to Christmas Island in Kiribati (pronounced Kiribus I am assured).