You'd have to find a real niche for these. It's becoming more and more scarce to find someone who uses them as they are being replaced by Digital Computer drafting programs and cheaper, disposable, fiber tip drafting pens. Most of the drafters I have worked with in the past 10 years or so don't even know how these pens work. Being that it is a type of fountain pen it requires the same, if not more, maintenance than a traditional fountain pen.
If you made one, you'd have to get the correct cartridges if they are available or build a custom body to hold the ink. I have two vintage technical pens that have piston mechanisms built into the pens (similar to the twist converters commonly available). These still work and have interchangeable tips like the top photo but this type of pen has just about gone the way of the dinosaurs.
I think you'd be hard pressed to find a drafter or artist younger than about 50-60 who knows how to use one and is willing to put in the time and effort to keep them maintained.