I don't know what year and car (fairlane?) you need the harness for. Alloy Metal Products makes excellent reproduction mustang harnesses, not sure what other cars they make them for. You can have your existing OEM harness restored by Welcome to Midlife Harness Restorations. Everyone on VMF likes his work.
I think Midlife can fix it, if you want to keep the OEM wiring. Another popular replacement that is well liked is american autowire, American Autowire Online Store I would contact them to see what they have. I would expect more than a months work for a good first time install of painless or AAW. A guy from VMF made the AAW instuctions at CJ pony.