Here’s a shop to add to your travel itinerary if you’re hitting the West coast: Rare Device, a funky shop in San Francisco (they used to have a location in Brooklyn too, but alas, it closed).
Here’s a couple of favorites spotted on their website:
A colorful notebook by O-Check:
And this is the birch tree notebook I recently saw at McNally Jackson, which turns out to be created by the owner of Rare Device: