Probably just splitting hairs over a semantics issue and not to start an argument, but I had always thought "NORS" stood for "New Old Replacement Stock". This would mean such suppliers as Western Auto, Sears and Montgomery-Ward (among others), who provided non-Ford replacement parts for years after the Model A ceased production. The need to distinguish between genuine Ford parts and parts made by aftermarket suppliers concerned the quality. Not all replacement parts were of the same quality as genuine Ford parts, or even half as good quality sometimes. Ford literature to its dealers made great pains to show inferior aftermarket parts that had failed because the owner hadn't purchased genuine Ford parts. One sees this especially in the Model T days, but also many times in the Model A Service Bulletins, complete with a picture of the dramatically failed part and a stern warning against buying anything but genuine Ford replacement parts.
Marco Tahtaras once pointed out that just because a part was NOS did not necessarily mean it was usable. When one talks about millions and millions of parts being made by Ford, even new parts were sometimes defective and were simply thrown back in the parts bin. They have survived unused because they were unusable even when new. It's probably a moot point in 2022 because who would install a genuine NOS part that an owner was lucky enough to find, unless it was on a high points show car that wouldn't see much real road use? A part can only be NOS once. As soon as it's installed and put into service, it is no longer NOS.
So, whether NORS stands for "New Old Replacement Stock" or "New Old Reproduction Stock", the idea is similar = non-genuine parts made by aftermarket manufacturers, whether that be in 1937 or 2022.
Marshall