Packard/Delphi systems is the OEM for the bulkhead connectors, I think I saw some repops but cant remember where. it was a website. You look them up by the number of "cavities"
I believe the packard-56 line is what your looking for. eg. http://www.pcsconnectors.com/packard56.aspx?page=2
If you are refering to a white harness connector near the rear of the right valve cover... delete it. It was added in the early 70s for ease of assembly only. Never should have been there in my opinion.