My most recent "insignificant" purchase was an NOS French threaded JPR headset. Insignificant as I already have a JPR French threaded headset in my NOS stash.
But I try to convince myself that this last one is significant because I have not seen one like it before, and it is totally different from the one in Velobase....
But then I only have one bike that requires a French threaded headset, and it has a Stronglight A9 on it that is original to the bike and looks like it will easily go for another two decades without replacement. So I am 2 French threaded "insignificant" headsets deep, presently.