Maybe.
The blue MP ones I bought from Kohler Dodge came with the p/n printed in white on the face.
Your NORS Prestolite has differnet stampings on the metal.
Standard Motors sold and still sells one that looks like that too. IIRC also unpainted but anything newer is probably not the same factroy as 20 or 30 years ago. :(
Don't worry about the other guy unless you think your so far under somone is buying it to flip it.
Are you making money selling it? Then sell for what you think is fair and moves it along. Unless you want to keep it for your collection