This is a simple, compact and easy to print holder for label rolls that fits right into the back of the Rollo label printer. I've included the openscad file so you can customize it in case your label roll is an odd size or the uprights fit a little too tight. As is the notches are spaced for 4", 3" and 2" wide labels.

I printed with PETG which worked out great since the flexibility lets me change rolls by simply bending the uprights out of the way.