Hello. Here in the USA it all depends on whether the boat was home built or it was built in a regular and reputable boat yard. No matter what, here, we can usually get liability insurance on anything as long as it passes survey. If you want hull insurance, it goes back to if some yahoo built it or a good yard built it.
The home-built ferro boats here are mostly so cheap compared to other boats that just having liability insurance is sort of OK.
Find a marine insurance broker in your town. The broker will have lots of companies to choose from. Your own boating experience makes a difference, too. Do you have any?