I needed to 3d print a lunch sack for a trophy I am making but there were no free options so I made it myself. I'm not here saying it's good, in-fact it's quite bad, but it's free. The model is really tiny so you'll have to scale it significantly in your slicer, sorry not sorry, it's free. You can do whatever you want with this, I don't care.
The texture was sourced here under a CC license: https://www.pxfuel.com/en/free-photo-xwdqm