Was your Challenger deducted points for the exhaust it was wearing at the time?
I've never been through the OE judging at the Nats so I wouldn't know the criteria.
Back then, as well as today there were dozens, if not hundreds of different manufactures making parts for the new cars being built by Chrysler, Everything from a single bolt to bumper brackets, carburators, seat covers, exhaust, etc...VERY FEW parts were actually manufactuured "BY" Chrysler.
By your definition, 99% of all NOS parts could be condidered "reproduction" parts.
Also by your definition, all parts manufactured and licensed by Chrysler would be considered 100% correct replacement parts.
So there should be no difference in point deduction unless the NOS part has the wrong date code or other details as mentioned.
This train of thought would be a huge relief for the OE crowd because every new reproduction part being made today licensed by Chrysler should be considered a ZERO point deduction. You can use those Chinese manufactured door handles, light lenses, sheet metal, etc...No longer a need to hunt rare NOS fan belts because the new Quanta belts will fit the bill !