This is a storage folder for folded backpacking maps, if you have Fusion 360 you should be able to modify its parameters to fit your needs, there is also an STL for printing a thin-walled folder (1.2mm walls, both external and internal) with space for 6 maps that fit a 9mm*140mm open compartment (it's 80mm tall, which lets my maps sit mostly upright).

I made this with ~no experience with 3D printers or Fusion 360 (I've dabbled in Solidworks in high school), so I licensed this to allow you to do whatever you want with the model. I'd like to look into reducing filament use without prolonging the print time too much.