Where to get lens screws

[Tristin]

Attempting to service a 200mm f/4 Ai ended very quickly when a mount screw stripped.     Looks like I will be needing to get a tool to extract stripped screws and a replacement screw, anyone know where to buy these on the internet?  Heads up, I have no local stores that carry lense repair supplies apparently.  Couldn't even find helicoid grease, had to order it online.

Yes, I have the correct screwdrivers.  Somone apparently tightened these screws far too tightly. 

[Bjørn Rørslett]

The AI generation lens screws are often kept in position by liberal amounts of Loctite. You need to treat these lenses with some solvent to soften the bond, or use local heat to break the screw free. Using the proper JIS screw drivers might not suffice on its own.

As to the mount screws, they are often different from one lens to another. In particular their length varies.

I drop in at my Nikon Repair Facility in order to have a focusing screen replaced on my Df and might lean a bit on my contact(s) to have them check the repair manuals to find the correct screw type.

[richardHaw]

Tristin, there is a portion of my blog dedicated to screws and screw extraction.
http://richardhaw.com/2015/12/29/best-practices-part-1/
i will need to update this with new information.

i get equivalent screws from screw factories here in bulk.