Good morning, Shawn;
The best place I have found so far for small screws is down in Anikin's Territory. Well, actually, not far from him up in Portland, Oregon. Parkrose Hardware on NE Sandy Boulevard just a little east of I-205 is were I have gone to get small screws. They have both US and Metric, mild steel, brass, stainless steel, round head, pan head, flat head, oval head, socket head, and others. Truly a place to warm Tim Allen's heart and set it afluttering.
While I do live up here in Latte Land, Washington, yes, I have driven down there just to get small scews, because I know that I can get them. While I have not been able to get a true exact replacement for every screw I needed, I have been able to get engough screws to replace all of the screws of that type on the camera so that it all looks the same again. In many cases, this has been an improvement, because the replacement screws were stainless steel, and I think they look nicer.
Others have already suggested Micro-Tools, Small Parts, hobby shops, and others, and perhaps even a local watch repair shop. I also suggest checking your local independant, non-chain store, hardware store. You might be surprised at what they carry, and I have found that their selection was better than "the large box stores."