I have built my own cable for my elderly Series I, using nice fat red (the better to see it on the floor on a dark stage) cable stock and terminating it with a sexy black Neutrik 5-pin XLR right-angled socket for the instrument end and a straight sexy black Neutrik 5-pin XLR plug for the power supply end. The reason was to get a cable of a more useful length for where I play.
Somewhere along the line I bought by mistake three extra straight plug connectors (Neutrik NC5MX-B), and did so too long ago to bring them back to swap for the 3-pin XLRs I really wanted (for an audio application).
Should you be interested in making your own cable (and I confess that soldering 5 wires to a connector correctly is damned tricky), I'll let you have any one of them for cost of postage. Shoot me a note with a request and a mailing address.