"In The List, does a NO under grips indicate non-matching or unnumbered? Is it possible that some of the NOs have one or more original but nonmatching grips?"
If a gun is reported with numbered but non-matching grips, I leave that column blank since there is no way of knowing if the original grips were numbered or un-numbered.
A note on the poll:
The percentage of guns listed with un-numbered grips is almost certainly low. Much of my information is gleaned from auction catalogs and dealer's lists, when a listed gun has un-numbered grips these sellers are silent, when it has matching numbered grips they shout it from the rooftops.
Best regards, Norm