I can images that some readers will be thinking "I've lost the plot!" But bear with me. I saw these Allura Nail Art beads in Poundland (UK discount store) for £1.00. The tiny round beads are perfect for small rivets - drill a small hole (slightly smaller than the bead) and glue in place.
The second image shows the beads a little better. So any scratch builders out there - especially Victorian Science Fiction modellers (who always need loads of rivets) go along to Poundland today and get your pounds worth of ready-made rivets.
Sometimes called Nail Caviar?