CAD designed and 3D printed, now I can actually find what I'm looking for.
US 1/4" drive holder
Metric 1/4" drive holder
Metric 3/8" small side
Metric 3/8" big side. The whole thing wouldn't fit in the printer, so I had to glue the two halves together,
Organizer from the left side of the photo, holds the 1/4" drive hardware
Organizer from the right side of the photo, holds the 3/8" drive hardware
Inch 3/8" drive holder