These are 2117 AD rivets. Use Wire size drill bits. Standard sizes are #40,#30,#21, and #10. Fractional bits will not size the hole correctly for your replacement rivet. Use high speed on your drill. Drill the head to where the point of the bit is into the shank of the rivet. The outer edge of the bit not quite through the head. This allows you to be off a little bit and not damage the structure. Take another bit of the same size and turn it around putting the end into the hole and snap the head off with a side to side motion. Drive the shank out using a pin punch of the correct size. Back up thin metal to keep from bending it. I hope this helps
Also do not use air hammers to drive rivets. They have a different stroke than an actual rivet gun. They can fracture the rivets when you drive them. If you need to use a blind rivet. Use Cherrymax rivets. They are a structural rivet unlike the common Cherrybulb rivets you find at a hardware store.