OK So no one knows the answer?
The motor which came off the model was an OS 155A. My research tells me that it is .155 cu inches, which equates to
https://hobbyking.com/en_us/turnigy-...-160-glow.html
I've no idea if I'm right, but I'm moving on to the ESC . . . Perkins 85 Amp?
Back to Google.