Hi Ian, it's a pre-war civilian model with the seat studs horizontal, cushioned handlebar clamps and fork side damper knob different from WD, front brake on right was for 1939 civilian model and forks would match to fit it. It has the narrow civilian tool box which is good
Rear mudguard section is wrong or has been cut short and the stays are missing, numberplate isn't Norton. It should have pedal footrests, it's got a WD rear mudguard loop with side-stand bracket. No chain-guard. It looks like the battery carrier is missing? Horn & speedo missing.
All easy to sort out. I would say the rest of it was original. No broken fins which is a plus
That depends on whether you're a member of this forum or not
A genuine civilian model is rarer than a WD model. Most bikes that claim to be civilian models are in fact civilianised WD models.
One other point I was going to mention was that the tyre inflater lugs had been cut off the tank, but this would be correct for a 39 model as it was put on top on the chain guard.