After looking for one for a long while I finally found an unmolested Nishiki Cresta (sold as a Repco in Australia) being sold by the original owner.
This one is in great condition for a 39 year old bike, importantly it has the Suntour driveline intact including the Mountech 3 pulley rear derailleur.
I won't be changing much from original apart from the seat and pedals that I've already swapped.
It's just a lovely bike I'm happy to preserve.