Found this helpful bit about boat insurance.
Checked out progressive just to see what they charge. I read the details for each section of coverage and it looks like you need more than liability to have them cover wreckage removal. It's only covered under the "collision". Still, it only ended up being a few hundred bucks with the most liability I could get and a good amount of comprehensive stuff. What a relief. I guess it pays to have a boat that's not worth a whole lot?