When I bought the harness for my '38 I shopped both Road Island Wire and YNZ Yesterday's Parts. I found YNZ to be a tad less expensive & good quality. Shop both before you buy. YNZ sells wire and components as well as harnesses. A lot of people praise Road Island so they are likely a good source but I've not used them. I'm happy with my experience with YNZ.
http://www.ynzyesterdaysparts.com/
