I love my guitars, but I have to ask...
If you know nothing about the N4, why on earth are you even considering buying such a high-end guitar? -- & I assume online as well, so not merely unplayed but sight unseen.
There are plenty of used USA-made N4 listed incorrectly as "Custom Shop."
There are plenty of N4 that were built in short runs for shops such as Funky Munky or Boogie Street. I've seen more than a dozen different finishes.
Now that the USA shop is closed, I don't know whether Customer Service would have access to those records.
The model is becoming very popular for counterfeiting. I can get a fake N4 for <$350. That sounds like a bargain to some people, but fakes are generally inferior materials, cheap hardware, poor construction.
Speaking for myself, I'd never buy an N4 without at least having it in my hands, preferably allowed to take it apart to check details, but likely with the assistance & approval of an experienced luthier at a credible guitar shop. I'm not wealthy enough to risk thousands of dollars on what might be an unplayable illegal copy.