Did you try numrich for screws?
I got one of these sets https://www.amazon.com/Wheeler-Professional-Gunsmithing-Screwdriver-43-Piece/dp/B00HTN4EWG
and took the bits that actually fit the screws on all my guns and put them in a small thick ziplock bag with a glock punch and a .035 and .050 allen wrech (for overtravel adjustments). I feel like if I need more than this something is took fucked to worry about at the range lol.
Pro tip: spend 25-40 bucks and buy some hollow ground screwdrivers. They spread the pressure out evenly in the screw slot and help avoid damaging impossible-to-replace screws.
You should use the right size flat screwdriver, both width and thickness or you risk making gouge marks on the screw heads. Here's a reasonably priced set that should have the size you need.