Well, I looking around at some things. What struck me is that they are flat-sided like carpenter’s pencils. So I was looking for drafting or art markers because someone might use them on an inclined desk. Apparently people aren’t in the habit of selling old markers–not much luck. However, looking up highlighters did show some things that looked intriguing.
Staedtler Textsurfer Classic Highlighter:
The “Classic” suggests it’s been around awhile.
The other prop that has a sort of angled cap kind of looks like these Stabilo Boss Highlighters:
The “Original” also suggests they’ve been around for years.
So those are some suggestions to look into for vintage versions.