2000 Oldsmobile Bravada wiring

I bought a Bravada a few months back and a small heater hose deteriorated and caught my wiring on fire, and I have been trying to find another complete wiring harness for this truck. The problem is that this wiring harness from the dealership is discontinued and can't get one for less than $1,800! And when trying to find a complete wiring harness from anywhere else they are only one strip or piece and not a complete wiring harness for everything. With all the color coded connectors as such that plug into the ecm module (computer) and all the other plugs. So, in short, I need to know how to find a complete one either aftermarket, or how to tell a salvage yard what it is I am looking for, or if there are ones I can get out of another vehicle and what vehicles are acceptable to get one out of? Every time I ask a salvage yard or look one up online they are only one strip and not a complete big main or total wiring for the engine that I need! Hope this is enough detail for someone to help me PLEASE!