You can try Hill & Usher, they can set you up with an underwriter (they are brokers). They can provide liability as well as hull insurance that includes water damage, theft and a few other things (for theft, you would have to provide a police report, FAA sUAS registration#, serial# and sales receipt). I'm currently paying 10% which is $100 per $1000 for the hull (includes anything to do with the drone like electronics, frame, etc.).
Liability depends on what you're doing and if you need insurance for things like lawsuits for privacy matters.
I'm currently paying $2300 per year for the whole package with $1 million liability plus privacy insurance. I have hull insurance on 4 drones which is $1500 of the $2300 policy, that leaves $800 for the liability and privacy part. 2 of my drones are older so fair market value isn't that much at this point (an older S800 and an S1000 that's a couple of years old). The other 2 drones are Inspires, 1 is an I1 V2 with an X3 and the other is an I1 Pro with an X5R.
There are several different packages to chooses from. They require an informal experience level affidavit which is easy to do, no proof needed and you don't have to be performing commercial work at the time. It's basically drone aerial photography insurance with hull coverage.
Even if you're just shooting stock footage for future use, they'll still provide a package for you.
I've had good luck with them and they are very helpful.
There are many others out there, Hill & Usher just happens to be the best one for me (IMHO).
Doesn't hurt to give them a call, they were issuing drone aerial insurance way before the 333 process started. They didn't offer hull coverage back then but they do now.