I decided to do a little project which really needed to be parametric, so I slogged through learning basic commands in OpenSCAD. It was actually a pretty interesting way to think about 3d design.

Here is a card box template with lid that can be used for any size cards, sleeved or unsleeved.

Measure your card or card sleeve in mm.

All parameters should be self-explanatory except maybe extra space. That is a little bit of extra room left between the lid and the box to make it fit a little bit easier. Play with that value for your specific printer. Note that it applies it all the way around the box, so a value of .2 will actually be .4 (or .2 for each side).