From what I have been able to understand from the documentation, this car was in no way produced by the DHMC. They did experiment with twin head lights but Geoff Healey says the body parts in question were removed from the car, the chassis of which was then used for other purposes. he also said it didn't have flared wheel arches.
The only connection this car could have with the DHMC is that it uses the double headlamp wings and shroud from the DHMC version as these parts were sold off. Presumably they were installed an a 'normal' Healey which was then further modified, including the rack and pinion steering and the 4 inch wider track, none of which had anything to do with the DHMC.
How much is it worth? Who knows, as a good condition, modified Healey, maybe 60,000 ....but 225,0000...don't think so.