Print the indicated number of parts. When assembling the part where the top slides to, must be towards the center of the box. This way it will be impossible to accidentally open and spill the contents of each card/train box. In other words the notch to pull the cards out must face the center of the box, never the walls. Check the images for the assembly. This permits the wood standees for the cards to not go around.
If you do not own a 3D Printer you may order it on https://3dprintforgames.etsy.com/
The author marked this model as their own original creation.