Well, it doesn't look normal to ME, but you have to consider that I've only been in the hobby since March. Maybe heat marks like that are normal in some cases. It should still work I think. Nothing is broken obviously. Get a set of the odd-sized head screws and put it back together.
I checked www.mcmaster.com and you're right M3.5 is crazy hard to find.
The RB WS7 screws are the same, if you can find that set. I think Hyper set is more common as you'd have to import screws for France for the RB's and that's just silly.
-Rob
This is a kind of silly idea, but you could drill and tap M4 threads into the case and enlarge the screw holes in the head. You'd have to have big ones to drill and tap your case though. If you had the curage to do it, you could then use 4x14mm screws. *shrug*
I checked www.mcmaster.com and you're right M3.5 is crazy hard to find.
-Rob
This is a kind of silly idea, but you could drill and tap M4 threads into the case and enlarge the screw holes in the head. You'd have to have big ones to drill and tap your case though. If you had the curage to do it, you could then use 4x14mm screws. *shrug*