Field Notes is probably what your looking for.

https://fieldnotesbrand.com/products/expedition

On your note about carrying a few notebooks: I was in this same boat. I carried a paper planner, a notebook for notes and lists, and another one with graph paper for projects (wiring diagrams, building floor plans, etc). I've been using a Midori travelers notebook for the last year. It's essentially just a nice piece of leather that holds inserts (think field notes type notebooks). I have 3 inserts in mine that cover those areas and when they fill up I can replace each one individually. I'm loving it and the leather looks really classy.

I really like the size and aesthetic of the Field Notes notebooks. Small and thin enough to fit in a pocket. Maybe not as durable as some might be looking for. I kind of like the weathered look they get after some use though.

For something larger and more durable, I've liked these Miliko brand notebooks. The paper is nice to write on and doesn't bleed through.