Paper Junkie Pocket Notebook - 12-Pack, 2.7 x 4.5 In, Brown Kraft Cover - Composition Book for School & Office - Travel Journal with Top-Sewn Flat-Lay Binding

https://www.amazon.com/Pocket-Notepad-Paper-Notebook-2-7x4-5/dp/B07R567588 These are what I use, cheap enough that I consider them completely disposable 🤷 Edit; I trim/fold back about a half inch off the back craft paper back so it sets down and the fold matches up to the wallet. I used to cut the rest of it down (using the printed lines as a handy guide 🤣) too so it didn’t stick out of the wallet a bit, but don’t bother now as I go through them quick enough they don’t get too dog-eared before they are ready to be replaced 🤷