You should ditch the crummy screws that come with the servos and use these socket head servo screws from Micro Fasteners instead: https://www.microfasteners.com/stw03...al-screws.html

They have an assortment of sizes available. My only complaint is that shipping charges to only buy one or two items can be expensive (as compared to the purchase price of the item itself), so I usually wait until I need a bunch of stuff and stock up all at once.