I like the idea too :)
Bearing Wholesalers and another local bolt shop don't have them that small though.
Needs to be 3mm hole and minimum 8-10mm size washer.
Need to head into the big smoke = Bayswater :)
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If not I'm sure you could make some. You'll need to put heaps of rivets into it though, they need to be close together
You can get quite large heads on rivets if you require it. You might get lucky and get one with an 8mm head.
What about nutserts?
Why not make your own with a hole saw ??