The whole boat, hull & deck was made of wood. The deck was covered with an impregnated canvas-like material in hih traffic areas
As delivered, the PT-109 was painted with a gray hull & superstructure, 20B Deck Blue Deck, and Copperoid (Hull Red) on the hull below the chine.
Operaionally & as lost, the PT-109 was painted overall in a South Pacific PT Boat green (hull & superstructure). The lower hull remained the Copperoid.
The most accurate choice for these colors are in the Colourcoat line of paints from White Ensign Models.