wiring harness for Ford F53 fuel pump

I have 1998 Holiday Rambler with 1997 chassis. I replaced the fuel pump and need the 4 wire harness to connect fuel pump to my existing wiring. The Ford part that I need is #F7PZ 9A213 CB and Ford no long has this harness. Apparently the wiring harness switches from one end of plug to other end. Motorcraft has part#WT56821 and they don't have part either.
Any suggestions as to where I could get harness or purchase one from Company that makes special harnesses that are out of stock.

Thanks