1971 NRA Centennial Musket|Winchester Rifles|Forum|Winchester Collector

I have recently developed an interest in the NRA Centennial Musket.  According to Blue Book of Gun Values, 23,400 were manufactured, but “not all shipped”. This begs the question, and maybe a foolish one, but if all were not shipped where are those that were not shipped?  Stored away?  Disassembled for parts? If they are still in existence can a distributor obtain to sell to dealers?  After 45 years would their condition likely have deteriorated so that purchasing one would not be a good idea?  thanks