Clear picture of the engine number shows it not to be applied by Norton.
The crankcase has no 79 x 100 marking as well so likely has been an unnumbered spare crankcase.
Framenumber a bit dodgy as it appears to be on a flattened surface. Better picture required of a cleaned up area to have more certainty.
Whatever the numbers, it is an ex military 16H but need loads of TLC before it is on the road again.