You didn't say what year (the partsnmore one is only for 73-75)
Complete harnesses from stripped bikes for a specific model and year are usually available on Ebay and the like for much less but you never know what condition you are going to get.
I found that I got good results by fixing up the one that I had.
New connectors and housings may be got at:
www.vintageconnections.comWatch the housings. The lock tab is on the ones I got were the opposite to those used on my bike (78 750K)
Depending on what the PO did to yours, various techniques to repair might make sense, or not. What is the problem(s) that you are having? Making a new harness might make sense for a heavily modified frame but if not, why embark on something that could be quite complex?
Are you comfortable with electrics and the techniques used?