There is no such thing as a make or model specific insurance company. Just find a reputable classic insurance carrier that's underwritten by a reputable company and get an agreed value policy.
Used to be Footman James----with such a rare classic expect additional restrictions such as annual mileage limits,agreed valuation, independant expert pre inspection , secure garaging etc etc--- many mainstream companies won't quote you at all.
Hi there and welcome. Try the specialist side of brokers A-Plan. They’ve done a couple of unusual cars for me, including a classic Ferrari. I use the Newbury office even though I’m not based there. At least you get to talk to a real person about what you need. Good luck.