Wait a moment. It is me or that's the MSRX landing gear?
That gives us a pretty good reference for size: it's a CP version of the MSRX. At this point it could even be a hoax.Who knows?
Edit: after sophisticated spannometric measurements on the photo posted by zadaw, the main rotor diameter should be in the 181mm range, just like the msrx and below both mcpx (245mm) and miniCP (240mm).