Just use FreeRefills or a similar addon and it will auto-restock for you when needed.
Also take a look at FuBar_PTReagentFu.
FuBar_PTReagentFu is good, and is a fine replacement for FuBar_AmmoFu.
FreeRefills doesn't seems to be the right thing for me. It's not auto-restock I need, it's the warning indicator in UI. And auto-restock doesn't work for potions and such where I have to switch to another character to craft.