I believe Robar also does a finish referred to as Polymax, a dark matte polymer coating...impervious to corrosion, but no where near as pretty as NP3.

I'd also search for Checkmate gun refinishing, I believe they are based in Florida...a review on a Beretta 92 finished in hard Chrome a few years back showed the hardness of the finish near 72 Rockwell. The gunwriter claims to have dropped his pistol on concrete accidentally, allegedly leaving no marks on the finish.