the thermo is in the oil filter adaptor housing on the side of the block. it's a simple little device but if an attempt is made to block off the oil cooler and run an engine without it, the oil pressure is diverted straight to the bearings etc with out going to the filter.
Paint codes are on the option plate with 3 digits and either G or H next to them (g=glasurit and H=herbert.) All of the colours are easily available from any paint supplier. The original type cooler is lifted from the car with the radiator .