You can't buy them! Nikkai is a brand sold only by Maplin and they don't sell the wiring harness or a connector to fit the stereo!
Only chance is to find a connector that is close (Pioneer/Sony/etc) and use it to make your own harness, but you need to know the pinouts at the back of your stereo. They may not be the same as the big name brands.
I'm trying to get pinouts for an A86FN cd player!
Steve Wilkes, July 2012
