Gotta say this is one place where Inland Andy has a good no-brainer. Go to http://www.inlandrv.com/parts/
and scroll down to the part number below.
79015 view part
Drill Bit Kit 3 - #30, 2 - #21, 1 - #11 (stubby) per kit $7.95
The 3 smallest are for 1/8" pop-rivets -- multiple uses on interior and exterior. The 2 mid-size drills are for 5/32" and Olympics. The good thing about this set is they are short twist drills -- if the rivet pushes in suddenly (as will happen!) you can't poke through to the opposite skin!
I've found it difficult to stay on top of a round rivet to start drilling it out unless I dimple the top with a Dremel first. And with a Dremel I can use fine grinding stones and rubber polishing wheels to smooth the rivet -- saves the shaver cost, though a critic could look closely and probably tell the difference. My polishers are pretty standard dental lab stock.