Heavy Barging to Islands

[SaukeeToMe]

I'm starting to consider a structural improvement (stabilization) project for my camp on Rattlesnake Island. In exploring my options I want to understand more about barging equipment and materials out to Rattlesnake. In the least I foresee needing a bunch of concrete and likely some crushed stone for drainage improvements.

What if I wanted to get a truckload of concrete to the island?
Is there a barge on the lake that can haul a 70k lb load? All I can find is that 30k lbs appears to be the max from https://www.lakelifeservicesnh.com/winni-works-barge

What does it cost to get a barge to Rattlesnake from West Alton?

Any advice or warnings or perspective on Island construction and materials/equipment transport is much appreciated. Obviously, on an island less is more, but 'something' is still necessary.

Thanks.