It bothers me that only one of my screws (yellow petzl) is missing a cap. Bought it for like $20 covered in rust and cleaned it up…. But no cap…
I’m sure there’s some clever way to make your own, melting a plastic sleeve or something like that, and I’m sure that one of y’all smart people has already figured it out…
Just get a nice sleeve type carry bag for your screws and then they just live in there, no cap required.
I use one of the bags from High Mountain Gear. It drains wells and the screws can dry out whilst in the bag, I just pop open the top. Minimal fuss/organizing and they're always ready to go with no pesky caps.
I ordered several hundred vinyl end caps from McMaster-Carr for like $10, looks like the order I did was "Round Caps for 3/4" to 13/16" OD, 1-1/2" Inside Height, Black 9753K55". They fit really well, haven't had one fall off like the petzls do.
Not helping the OP, but I second the "screw the screw caps" comment. I'll use one now and then, when I have one or two more screws than my screw pouch can hold (so no harm will come to other gear in my pack). Other than that, they're a nuisance serving no useful purpose (IMHO).