Maybe Painless Performance? Those harnesses seem to run about $500 though.

Rewiring an entire car is a non-trivial job. I just finished wiring my '72 Dart by hand, from scratch, and I will never do that again! The number of wires and connections even in a "low-tech" car is amazing. Although it did give me the opportunity to add relays instead of running all the current (such as headlights) through the switch and harness...