I like most of my gridfinity stuff stackable. While the original model is already for a gridfinity-setup, there are no bins dedicated for this spools. So I made a version, that fits up to four spools in a 2x1x7 stackable gridfinity bin. 

Beside that, I find the regular round solder-wick-"containers" in which they usually come very annoying. The model from @AndreasMass is lightweight, space efficient and fits alot nicer into the gridfinity-ecosystem constraints. 

This bin uses gridfinity-refined-style magnet cavities. if you don't like this, use “gridfinity rebased” to change the magnet-style.