I wish someone could tell me what to search when I want to look for vintage striplights, shoplights, lamps, and ballasts. Whenever I Iook for for items like these, I am bombarded by thousands of desk lamps. I don't want desk lamps.
Seems that most people think a desk light is the only kind of old fluorescent light fixture there is.
Yeah that is a problem. I have found that many times people are not sure where or how to list a fluorescent fixture.
I happened to find a 1940 Mitchell fluorescent shop light fixture on ebay in near perfect physical condition by accident just by looking around.
It is a beauty with the original paint.
It was not listed as fluorescent lighting but as a "florescent light".
So now I include "florescent" in my searches.
Sometimes they are listed as barn lighting, industrial, vintage, collector, antique shop lights but not always.
Sometimes there is no mention of fluorescent at all.

I was told by one old lighting dealer that they junk fluorescent fixtures as there is no market for them.

They just sell pendent lighting only.
I told them that there are pendent fluorescent lights too.
No response.

Seems that a chain hung fluorescent light fixture could be considered a pendent fixture.
But I guess not.
Seems you just have to look around and try searching everything.