While the actual riveting will be easy, it may be a fair amount of work to get to the repair may be extensive. Also, it looks like this is a two curve bend which is going to require getting a panel cut to match, then match drilling and even then may not lay flat. There is a lot of unsupported panel.

I suspect that there is something to seal water out from between the panels.

Also thinking down the road. Are you willing to take on responsibility if the replacement panel leaks?