Hi mate, I'm happy to tell you that this Spit was definitely in Dark Earth/Dark Green camouflage! I found the same pic you've linked to,(attached) in a much older, differenent book and, although it definitely looked to be in the Green/Brown, I nevertheless 'read' the half-tone dots, to establish the likely tone/colour range against a grey scale. Green/Brown it is!
The article on the model, and the RAF.0rg chart also show the correct colours.
Spitfire RN218 was a FRXIV, built at Aldermaston, and, via 2 MU's, was shipped directly to India, arriving on 30th August 1945, after hostilities had ceased. She would have been painted in the SEAC colours at the factory. The aircraft was on charge with ACSEA from September 1945 and, although I don't have an exact date as to when she joined the strength of 273 Squadron, we can assume it was November 1945, as this is when the Squadron re-equiped with the MkXIV, until disbandment in January 1946. The aircraft was Struck of Charge in March 1947.
Note that RN218 is a FRXIV, and not a MkXIVE, so should have the camera port and hatch on the side, behind the cockpit.
I hope this helps mate.
Terry.