Not trying to push you down the ZX6r route! but Maxton have already re-valved a few sets for RGV's and I would imagine the spring weight etc wouldn't be too different.

I have to say though that I really like the RWU look of the NSR forks and only went for the ZX forks as the RGV already had USD ones. Have you thought about a maxton re-build of the forks and shock? it would probably transform things.