https://www.matchlessclueless.com/mechanical/identification/frame-number/Finding the number!
NC1 is tasty, speaks to Comp motor maybe, but I was expecting the engine number to include a date. The fact that's it an NC1 as opposed to a standard N1 doesn't really mean a whole lot absent other data, but they are sought-after instruments with a 'ringcam' as opposed to the face cam of the std version.
Think you could benefit from the Club dating service and advice from Singles Owners over 'there' in that paralllel world as it were - and if you care they can tell you year of both bits usually, although Comp models can be harder.
Whatever it is is or was, I think what you have there is a really good base for a very usable bike.
Twin downtubes came in quite late, '59-ish, and the chaincases are nice. Alternators were adopted earlier than that on some models.
Brain fade prevents my saying which years had the torpedo side lights, and indeed a whole host of other things.
I'm just glad mine of the marque ('54 and '61 twins) are complete and work, always have and with any luck always will - and I don't mind too much when folk tell me bits are 'wrong'. I know that.
'Where's Yours, so I can Compare' is a good riposte I have found, even if it doesn't win friends when the audience doesn't have anything that actually, er, works. (But not many people have a three-owner 'half million miler' in their shed, like my disgustingly grubby Mod 20 twin).
Even my much-loved recently-departed A10 couldn't match that, although its new owner came round on it just yesterday as it happens, and said he couldn't believe how reliable it was after a good few thousand miles without needing to touch it. Which he clearly hadn't - it was 'first prod' every time)!
Much - No, correction, a LOT - to be said for 'unrestored working bikes', where a little bit of available money goes into the guts and none elsewhere. That Ajay would be a fine member of that increasingly rare class.