Irian jaya is the Indonesian side of the island of New Guinea. If the Big Al's description is accurate, it could be a New Guinea datnoid, Datnioides campbelli, aka NGT. The price is cheap for an NGT though. Here's a picture I found online:
Two types of Dat are found in the Irian Jaya region taht I can find reference too, one is the D. quadrifasciatus, that is the more silvery one. The other is the less common D. campbelli and that is variable but tends to be darker and more orange.