#1
The screw used too tune the intonation of my GRX20's Low E string has a barren head. Seems like the metal those screws are made of are just too cheap... probably combined with some mishandling of my own. I was wondering if there was a standard size for those screws, so I could just go and buy them at the hardware store. I've seen replacements for stratocaster saddles sold on some websites, but they're fairly expensive (for screws) and I'm not sure if they'll fit.

For reference, the (blocked) tremolo unit/bridge should be the FAT-6/C.

If I were to just change the saddles themselves, which would be a good upgrade? Also, from some researching, I saw there were "USA" sizes of saddles and "International" sizes of saddles.. what does this mean and which guitars would be compatible with which?

Thanks, good people.
Kaguya: Ibanez GRX20 - Coil-split handwound Humbuckers
Isabelle: Fender 50's Road Worn Strat signed by AutoVaughn
Selene: Ibanez RG2EX1
Blackstar HT-5
#2
I guess no one really knows..? I think I'll just buy the saddles that "fit Asian-made guitars" on Guitar Fetish.
Kaguya: Ibanez GRX20 - Coil-split handwound Humbuckers
Isabelle: Fender 50's Road Worn Strat signed by AutoVaughn
Selene: Ibanez RG2EX1
Blackstar HT-5