The Kakadu, very similar in size to an Opera Master, was part of a trio of pens exclusive to the Australian market: the Australis, Didgeridoo, and the Kakadu.  It’s a wonderful, well-balanced pen with a great oblique stub nib.  This is the pen I took with me when I defended my PhD thesis due to its great balance and reliable writing qualities.  I have not yet recorded a full review of this pen but I will do so as soon as I can.