Just been on to Adrian Flux
£400....but that is with protected NCB and for an extra £60 they can add a "total loss" policy which pays out an extra 25% on top of whatever the insurance agrees if the vehicle is stolen/written off.
So let's say I think our Defender is worth £15,000 as it is immaculate and that's what similar really good ones seem to sell for. Glass's Guide says £11500 though, and after some argument the insurance offers £12,000. The extra policy then pays out £3,000 on top of that so you get a total of £15,000.
Worth having for peace of mind I think, just in case the worst should happen.