Just bought "The World of Kong - The Natural History of Skull Island" in Reading's 99p Store, might be worth keeping an eye out in the rest of the chain stores. It's published by WETA, and although it doesn't have stills/photos of the flora and fauna from the movie, there's still plenty of eye candy for inspiration.
The same store has got plastic aquarium plants in stock as well, you get 3 or 4 per packet, cheap source of jungle terrain!