The P-64 has the angled wingtip as well so, my final call, is NOT a P-64, but a Wirraway altered to look like one. I'd put money on that.
You misunderstand me KK. I'm not saying its one of those, I used that as an example of how the airframe can be altered to look like something else, and the P-64 is a lot less radical a mod than a Zero.