Not had an RS for a while now and wasn't considered a classic back then, but who would be best to try for Classic Car policy on my 1990 S2 RS Turbo now?

Previously used Need To Insure and Greenlight in the past, will try these again but any others for limited mileage policy I should try? Also, prefer an agreed valuation to save hassle

Car is standard apart from a S/S exhaust