Rhodia and Clairefontaine are cheap (the notebooks with simple covers) and they are the best for fountain pen writing without feathering. Only surpassed by expensive japanese paper.
Where can you find Rhodia for prices similar to what GP was talking about (brands aimed at students)? Those are typically under $4 - Target has several under $1.
Clairefontaine: Same question. I know it has a great reputation for fountain pen ink, but I had bad experiences with it. In a sense, it's too good. Line strokes tend to be thinner than most other papers. I can't write on them with my F or EF nib - I get a lot of skipping. Others have had the same experience - the paper is just not at all absorbent (hence absolutely no feathering).
I had a similar experience with Maruman Mnemosyne.
(Just my opinion - I know there are folks who love it).
I often use Figurare - it's similarly priced, although some of them feather more than others. I just tried Denik, and it's decent. Not as smooth as Clairefontaine (nothing is!), but handles the ink well enough.
I’m just dipping my toe into the “expensive Japanese paper” (TomoeRiver, Midori) and I think the experience (while writing, and ink-fastness thereafter) might be worth it imo.
