You don't need CAA approval for a NQ once you have a PPL......just a CAA certified examiner. Same for licence conversions, IMC etc....
It'll cost you say 5x $75 for a 172 and 4x$45 for instructor (I forget how many hours instruction are needed) = $555 which is roughly £280.
I asked the CAA if I could have a NQ based upon my American licence.....I have about 20 hours night. They said that I needed an amount of "minimum training to be determined by an FTO"..what a load of bollox.