If you are going to rivet your chastity device on at least use a quality rivet. The aluminum rivets which come from the local hardware are cheap and do not take much to open them. A quality rivet to use would be a cherrymax rivet. I have drilled may of these out of aircraft over the years and well they are no joke they have a hard metal insert and are almost permanent. The only other rivet to use would be a solid rivet.
My wife has replaced my lock with steel wires covered with epoxy adhesive It's permanent I will have to cut the locking post to remove my cage
Wife uses the cheap Chinese wolf dog padlocks then throws the keys away as they don't tend to open any way after getting wet for 30-60 days worth of showers, we now have a small pair of bolt croppers for lock removal.