Hi Mike,
I really don,t think it is a Dutton, I would have to agree with DB6 that this is a one off, and I think it would be a UK car being RHD.
It is very well done though.
I think the stock Caterham (and oft copied)rectangular box rear lights look like something you can pick up in a "build your own trailer" parts store.Ugliest parts on the car in my opinion.