Cylinder-slide.com offers a cool SFS system for P35/HP type models.
The Safe Fast Secure design allows the pistol to work a lot like a single action but you carry it hammer down(safety on).
I looked into buying a factory new FNH Hi Power 9x19mm in the mid 2000s.
If I had the $ I would have picked it up.
See Karl Sokal's Chestnut Mountain Sports in VT or
www.cylinder-slide.com about custom HP work.
CF