Deck Book Holder + Smaller Version

I like to play Magic: The Gathering, but I often find it hard to carry my decks around along with cards I want to trade or use outside of a deck. So I roughed out the idea to create a 3d printable deck holder to grip onto a standard 3 ring binder. This would then occupy the third (right-most) column of the card sheets that would be used to store extra cards.

I mainly eyeballed a lot of this project, but the dimensions of the interior of the box should hold up to 60 cards in tournament sleeve