You might start with stating why you want it, & then go to an insurer & ask them. Such as Pantaneus, or one of the other notables. Also, try a few different sales agents, including in different countries. Including talking to say, a US agent, & telling them that you want/need the information for when you take the boat
to the EU, temporarily, or permanently. And that having it will make it much easier to sell later, not to mention insure.