Nova in the UK made five speeds sold through Hitchcock's. I have one. Outstanding except for the fact the lever throw is as LONG as the original. But it is otherwise completely modern, bulletproof and smooth. Huge improvement.
Front brake is a Norton product both the 1969 SLS and the 1970 TLS. Neither impress, you can put a Commando disk on as I have, makes riding a lot less stressful. The last bike, the Series2, is the dry sump with Concentric Amals. Bike is detuned compared to early ones. No doubt to get it past the warranty period. Bike is really a 50's bike in feel and build. Let down by a weak clutch
(although very sweet to operate, cannot take any beating). Bob Newby offers a rugged lightweight clutch with chain or belt. The Albion gearbox is more suited to a 250 side valve and worst of all, the oil pump, which falls short if the ambient goes over 60F. Just not enough flow and pressure.
They are good looking, unusual and actually pleasant enough to "just go for a ride" on. I venture out on mine regularly, but fast
long tourng, no. Others do however. I suspect they own a tool room and a good disposable income.