So I did a thing!
I caught the jigsaw on sale for $10 at Harbor Freight… The Aluminum piece is a sample for some of our material we use here at work. I’ve seen similar shaped piece at Home Depot. You would have to cut them down and drill the holes for it. I use it cause it was free. The great thing about this is the paint bottle rests against the bolt at the bottom, the Velcro holds it in place horizontally and the rubber band holds it in place vertically. Now I will warn you it is not silent… but well worth it. I did a test on a paint i had not used in over a year: 1-Right out of the bottle, 2-Hand shaken, 3-Jigsaw Shaken. And I can tell you what, that jigsaw shaken bottle was FAR better than I thought it ever was. I mean I really shake them well when i do it with my hands but not nearly as well as that Jigsaw.