| I've got one that I got from Alan at AJ Racing (no longer trading cos he's got a race team job). Not branded in anyway so can't comment on that.
Central nut makes it a breeze to adjust.
Not sure if you'll find one at the NEC though, and they're pretty cheap anyway.
Call Craig at MotoRapido, as they had some in stock last time I was in there, and I'm sure he'll cut you a deal. | 
Threaded Mode