The frame is a later one - the wrap around headstock support with the hole for the wiring harness was a 1961 season feature. The number would have been stamped on the wrap around on the left side like the photo. Note the frame in the photo is "FA7" because it is a factory replacement following, I presume a crash.
If your frame has provision for 2 rear brake cable stops and for a rod brake pedal pivot on the clutch side then it also is a factory replacement.