These are the products I hope to have soon.
First the comparisons

The colors are different for the materials. This is about as good as I can capture the differences. The bolts of most your bikes are zinc plated. The anodized piece is anodized silver. I don't have anything that is nickel coated, but the stainless is somewhere between nickel and chrome. Neither the anodized or SS will rust.
ALL of the following anodized pieces are available in silver, gold, blue, purple, red, turquoise and black. The color does not affect the price.

These are the Cup washers. They take a standard socket head (Allen bolt). It adds minimally to the "footprint" of a standard socket head ... marginally less than a flanged bolt. Remember flanged bolts are only used so the finish of your covers is not damaged by the tools you use for installation ... Allen bolts don't have this problem. The gold (5mm), black (6mm), silver (8mm) are about $1 each. The blue one (10mm) is about $1.60.

This picture is the "top view" of the cup washers with a button inserted. NOTE: the color of the large cup (turquoise) is more accurate in this picture. The picture on the left has the blue button - it's color is close. These buttons all have a small 'O-ring" that hold them in - they aren't going to vibrate out. They can be inserted into any Allen head socket - but I don't recommend using just the silver on a "un-washered" bolt. The reason is that there is a color difference - it can been seen ... I think if there is going to be a contrast ... make it a big one.
As you can see the cup washers add almost nothing to the footprint. The buttons are about $1 each except for the purple one (10mm) - it's about $1.60.

These are the tapered cup washers. Everything else here is available in 5mm, 6mm, 8mm and 10mm. These are NOT available in 5mm. The flange out is close to, or slightly larger, than a standard flange bolts. They are like the cup washers but are tapered out at the base. The 6mm is about $1.70, 8mm - $2.50, and the 10mm about $2.80. Please remember almost all your bolts are 6mm.

These are the body work washers. They take a countersunk screw (flat head). The silver one is 5mm, the black and red are 6mm, and the blue is 8mm. Because almost all body stuff is 6mm - I can get these in 2 sizes. The black one when placed on a penny - the penny rim will show, The red one when when placed on a quarter - the quarter rim will show. The 5mm and 6mm are about $1.60 each -the 8mm is about $2.50. I haven't decided whether I want to go with the anodized screw line - but they would be about $1.30 each. If there is demand I would. Stainless screws would be about .30-.40 each.

I was just goofy around ... this is what it would "kinda" look like if I took the black body washer, a stainless flat head, and a royal blue button. The white would not be white - it would be a stainless color. To do this it would cost about the same as putting in an anodized flat head. (without the button).
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