A surprise

While down south I was asked to help identify an NZ120 collection as part of an estate. While a large porton of it was Japanese wagons and locos, there were a handfull of gems. these included;
- A zinc etch Dx (2nd batch ) assembled by Kelvin barry.
-A John Rappard resin cast Dx.
-An RB Resin cast DFT.

There were also several Japanese steam locos.the standard 2-6-0 and 4-6-2 and then there was this.....

Now, this is a beast I've never seen before (which is saying quite something), and some research reveals that this is a B6 by kawai Shokai which unfortunately is long out of production.
The mech also shows that it is not a normal Japanese N scale loco as the motor looks like an old Bachmann 3 pole from the late 80's

Of real interest is the wheel diameter (8.5mm or 3'4") and the wheel spacing (12.5mm +13mm) which is not far off useful.
Unfortunately it is one of those things that is long out of production, and since this one is the first I have ever seen its probably as rare as hens teeth.