I picked up some props for the Parrot minidrones (Ariborne, Mambo and Swing) from eBay, that claimed to be the same size - about 66mm long. The hole diameter is only 0.8mm, so won't fit without drilling out to the required 1.2mm (or a smidge under for a tight fit).

But of course, they're puller props (designed to go above the motors in normal flight), and the Batwing needs pushers. No problem, just fit them to the opposite motors so that they turn backwards and push, or so I thought.

Nah. It's surprising how little thrust you get from a prop running backwards.

So next I drilled straight through the prop so that I could fit them upside-down. Success! Enough thrust to get the thing airborne at least. Now just need to wait for a calm day so go for some 'exercise' to a nearby field. :)