I would check the Soundings Magazine Insurance section or the posted ads. I dropped Boat/US after they jacked up my premium. I have AARP The Hartford for my cars and house. They have the lowest rates than anyone for them. I decide to check them out for my Pearson 36 (1973) hull value $45000. and they blew away the competition.
My premium is $367/year:
LIABILITY INSURANCE FOR THE FOLLOWING:
Bodily injury $2500,000/500,000
Property Damage $50,000
Medical Payments $10,000
Uninsured Watercraft $500,000
Deductibles $266/$500
Fuel Spill MaX $10,000/Incident Max $25,0000/year
$1000 personal effect
$1500 Custom Equipment
The Boat is dry docked from Nov 15th - April 1st
There is an Ins Company hooked up with the Brewers Marinas and they were reasonable.