NACA5 recommended length gives 56-320pF and 3.5-20uH. That Kimber cable is far higher capacitance, exceeding Naim’s recommended with just 1m, while the inductance would require 39m to reach the minimum. Although IIRC the more recent Naim amps are said to be more tolerant than the classics, I’d be surprised if they’re that tolerant!
Why do you specifically want to spend a lot of money on speaker cables?