Hi Greg,
As you know, I've written a bit about WASPS (Sheaffer sub-brand pen), particularly about those done in the celluloid pattern we call Screaming Souls in Purgatory.
The Sheaffer 1930's sub-brand story-- including pens with words in their barrel imprints including at least Univer, WASP, Vacuum, Vacuum-Fil, Clipper, or Addipoint-- is not superbly fleshed out even after decades of consideration by the hobby. Generally the pens are second to third tier pens. We are quite blessed to have a fair number of adverts and some catalogue pages (good thing Sheaffer was a huge company and actuall liked its sub-brand pens), but plenty of questions remain. i also note that in some cases a given "brand" imprint (eg. WASP Clipper) was employed not only on pens of different plastics but also on pens of different shape and quality.
The pens you discuss are found with bland WASP imprint (no further name such as "Clipper" or "Vacuum Fil") but also wtih WASP Addipoint imprint.
In general WASP Addipoints appear to have been the low end pens in the second tier world of Sheaffer sub-brands. I have some paper for WASP Vacuum-FIl, WASP Clipper and (approaching from the angle of plastic pattern rather than imprint type) for the "Screamer", Lahn, and "Circuit Board" pens.
I've no paper on the pens we discuss today. They do seem a bit fancier than the ultimately low WASP Addipoints that have steel nibs and chrome trim. These have gold-tone trim and apparently gold nibs, at least usually.
Don't know if they were a parallel production to the really crappy Addipoints or were slighly earlier products. I have a feeling, based purely on having handled many 1930's Sheaffer sub-brand pens, that these date to very late 1930s or even early 1940's, the tail end of Sheaffer sub-brand production. Though the trim is yellow, I have suspicion it is fragile gold plated, not up to the level of Sheaffer's better gold-filled seen on Balance and perhaps on some of the better sub-brand pens. These seem fragile.
They are found in two sizes and at least two different plastic styles--a marbled and a candy-mesh-- though I have to look at more pens to determine if the two plastics correlate to specific brand imprint variations.
I have one generally like this with a lower-set clip with a "W" imprint. Not sure how that links to the others.
Photo is below, then some final comments.
The red pen above is marbled. The others I believe are mesh pattern. The generally similar gray pen has a different clip.
I like these, as they represent another aspect of a field which intrigues me, sub-brand pens. But, they are relatively low-tier with lmited market. They can have bit of value in nice condition as most are found trashed.
Note that this info I offer is observational and indeed speculative.
regards
David