Three invented photographers, each specializing in the facial expressions of cartoons (plus Zippy himself), and each with an invented name — composed of parts taken from the lexicon of art supplies (both common and proper).
Notes on the names:
1. Ham Speedball pen. The Speedball pen trade name is the easy part of this. The ham is more challenging for me, but maybe it comes from the odd Pen-Ham pencil:
Bonded lead pencil with round barrel, twin oversize hammer/gavel style red erasers, number 2 lead and brass colored ferrule, making this pencil ideal for gavel or hammer related copy. (link)
2. Flair Pointguard. A combination of the Paper Mate Flair felt-tip pen with the Point Guard tip, also by Paper Mate, designed to prevent fraying.
3. Sanford Waterbase. Here we have the Sanford company:
Sanford is truly a leader in the writing instrument and art supply industry. As a subsidiary of Newell Rubbermaid since 1992, Sanford continues to dominate the industry, most recently by adding companies such as Eberhard Faber (1994), Berol (1995), Wearever (1998), the rotring group (1998) and Papermate (2000) to its already impressive roster of brands. (link)
along with water base paints and inks.
As far as I know, there are no actual people named Ham Speedball Pen, Flair Pointguard, or Sanford Waterbase.
(And yes, eggplants are in the “nightshade family” (Solanaceae), along with deadly nightshade, tomatoes, tobacco, and more.)