If you go to an Orchard Supply and Hardware (OSH), it might be a CA regional thing, they will sell you 2 SHCS metric grade 8.8 screws, say 6mm 1.0 x 20mm length for about a buck, maybe $1.25. Last time I checked, you can get a box of 100 for about $8.25. Of course, you don't always need 100 metric cap screws of the same size.
But you could buy a nice drill and tap set and just make everything on the bike the same size. Think of the weight savings when your tool kit is one allen wrench!
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