Z said:Happ Jones Victor was a Z50M Copy. there was a guy on ebay a couple of years ago that had 100 of those footpeg assembies and side stands in the correct length.
Good luck. They don't go cheap in Japan. G-craft makes a side stand for 6" wheels that could be modified. I'd take a Z50 sidestand and cut it down to work.
Jeff T. At minigunz.com (website is no longer active) has fabbed some of those in the past.