The original fit 57mm wide playing cards, not 63mm wide ones as suggested. It is also quite tall and has a generous base.
But it looks good and has a nice taper to help keep the cards in. So I grabbed it, embiggened it by a few percent, trimmed the base and the top so that it holds my Exploding Kittens cards AND fits inside the original box. (Well, the box is actually way too big - you can print 2 of these and have them side by side if you get an expansion pack).
card_holder.stl | 160.9KB |