It doesn't matter where the parts come from. I simply like the look of the HD BT gearbox.
Of course it has no advantages compared with a "modern" lightweight brit box. But these arn't to my taste.
I've paid an used adjustable transmission plate and the fabrication of the pulley mount to fit the 45 sprocket shaft. The rest I tried to build by myself.
I think this is not much more than you would pay for an english assembly.