If you run the game with HWTL then the data and data3d folders from the Hwtl folder seems to be the ones you want, although you could still use the standard versions instead.
Unpbo the O.pbo as well......and that should be about it, as far as official objects for islands go.
Edit: Re-read your first post:
The textures for the original islands are held in Landtext.pbo, Abel.pbo, Cain.pbo and Eden.pbo
The objects for these islands are in the Data3d.pbo
O.pbo holds the models AND textures for Resistance.
Planck