Replacing Floor Rivets

My new 16ft jon that I recently aquired, is made from only one sheet of aluminum, only problem is that the seats/benches were riveted down and they have busted loosed in the 40yrs of use. So they were rebolted by someone, but that broke the aluminum around the bolts on the bench. What should i use. SS bolts? with maybe a sealer? or a certain type of rivets witha sealer. These holews are rather large. Maybe 1/4 of an inch or bigger. What do you guys suggest. Sorry no pics. Camera was stolen when i walked away from my bag while it was open.

You might have a little trouble finding 1/4" smash type rivets (without the thru hole found in pop rivets). It'll cost a little more to use the stainless bolts, but may be worth it due to the ease of finding the hardware. I wouldn't be afraid to just use the bolts with a little silicone.

go to harbor freight and buy the aluminum brazing rods. Just use a propane torch you can get at walmart. the boat surface will heat up to 730 degrees and the rod will melt but the aluminum won't. It works so good you can fill holes in a beer can. Google it. you can see for your self. Some are expensive, but I tried the ones from HF and they work 12.00

Bassboy pointed me here for solid rivets - and this is what I would use.

https://www.grainger.com/Grainger/wwg/productIndex.shtml?operator=retrieveProdLevel1Index&prodLevelList=Rivet%257CRivets%252C&prod_level_selected=Rivet

If the link doesn't take you right there, just click 'R' --> Rivet --> Solid Rivets