Can you find a Chicago screw with a suitably large diameter head? Possibly with a grommet or smear of silicone to prevent water collecting in the hole?
I was introduced to them as an alternative to tubular rivets by a local sadler (horse, not bike).
I'm guessing there are other names for the same kind of thing, depending on application - no doubt someone on here will know?
Can you find a Chicago screw with a suitably large diameter head? Possibly with a grommet or smear of silicone to prevent water collecting in the hole?