If you are a member of Facebook, contact Julian Anderson, member of the MG Rover 260 V8 Owners and Enthusiasts Group there. He may some valuable information for you, since at one time in the past he had the car viewed.
I assume you are keeping your eye on this list: https://www.two-sixties.co.uk/mgoc26...-260s-FOR-SALE
, updated daily, but as far as I am aware there are no RHD R75V8s, other than the Ealing one and the £30k Hursley Hill Garage one, being advertised for sale at present anywhere.