Years ago I bought a set of aluminum rivets for wading boots. They had a dome head with a post. The rivet was about dime size with a domed head. You inserted the rivet in the hole and drove the post flush with the head with a hammer which expanded the rivet in the sole. They worked well. I didn' know the name of the rivet and have been looking all over the web for it. Turns out it is called an Aluminum Drive Rivet. Another option.
"Here fishy fishy."