Well, Eastern Beaver has turned out to be a very useful resource. This is a small operation based in Japan, and on their very well-organized website you will find a selection of electrical connectors used on motorcycles, particularly Honda bikes .... and as it turns out, Zero! At least the 2011 model S taillight connector.
Can't say whether Zero continued to use these very solid flying-lead connectors in later years, but the above referenced connector mates perfectly with the harness on my bike, for what it's worth.
Thanks for the lead, Brian!