I agree. Wanted to get my hands on some white onza porcupines back when i build this bike, but couldn't get ahold of them.
For my next project (GT LTS) i bought a couple of reissues of the Panaracer timbukII and Tioga Farmar John (along with some Ritchey Max Evo) for that classic skin wall look.
Probably the Zaskar will get these tyres as well, along with a black Tune seatpost and Tune stem.
black tune stem and post will look fantastic on that bike. i really like the tune cranks also....they have the same nice lines that cook brothers cranks have.