Not sure where you are...Have you checked out Boat Us?
https://www.boatus-insurance.com/ins...T.mc_id=100004
They have some programs including "agreed value" in case of theft or sinking or whatever...
I think in many regions State Farm and Allstate and some of the major insurers might help you out. Good luck. And remember, the Seacraft can be replaced - it's the liability that buries people...