This engine has a couple of different features; the deep dished flywheel and the magneto drive. I see it but I don't believe it. The magneto runs at twice engine speed! Never seen that before.
I have heard of alleged Australian Palmer engines before, but none proven to be made here. O'Donoghues were agents for American Palmer engines. It is doubtful that they made any, but I am prepared to be proved wrong.
The cylinder head is like a CLAE, but it would not be a CLAE. It's a mystery, indeed.
Eric