As an update, this actual car also wears a Citroen Sportiva logo, with the Citroen badge being a Slough-built example, and the Sportiva badge being taken from a special edition AX Sportiva that was laying around in the builder's garage.
So, the full title of this car could be a rather long Sammio Chevaux Citroen Sportiva, manufactured by Bay View Rods in Poole, Dorset, who are now also known as Sammio Spyder Recreations Ltd! All very confusing!! Here's some more photos of the car.