Source for screws?

[SleazyRider]

I'm looking for a sideplate screw for a 1907 Dreyse pistol, not exactly the kind of thing one find at Home Despot. It's the same thread as a metric grip screw, only a bit longer. Numrich is sold out.

Could someone suggest a source for small, metric fillister-head screws such as these? I really don't want to buy an assortment from Brownells and hope that the one I need is in there.

Thank you!