I was looking at the item database for crafting supplies
and several of the entries have a number in parentheses. For example, "Jacoby (CK) (25), NWN9(50)" or "Simmy (3), Fibba (3)."
These numbers have no explanation on the page but they look suspiciously like quantities. However, the listed merchants have no where near those quantities in their stock so, do they restock after you buy the 1 or 2 showing in their stock? Maybe they will continue restocking until they have reached the limit of (25) or (50)?
EDIT: Ah, I found the explanation HERE
. That IS a quantity, but it's the quantity of gold coins you get from pickpocketing the listed merchant. Bummer.