@sorgule welcome to the Tormach user forums!
Thanks for sharing these. I printed off another pen holder (stl linked below) that was spring loaded for a project a few months ago. It was a quick adaptation of this thing from Thingiverse. I found that it worked just as well without the spring as long as the drawing orientation was relatively aligned with gravity. Feel free to give it a shot:
sharpie_3 v1.stl (364.2 KB)