I used bar risers that gave me about a 1" lift and 1" setback and I was able to keep my stock cables. Sadly, they were made by a forum member who has since passed away. You might look at Helibars as I believe they also offer bar risers.
Twisted Throttle might have bar risers for the NT. One thing to keep in mind in although most bikes, such as the NT use 7/8" bars, the dimensions between the bolt holes for the handlebar clamps can differ. I'm fairly certain those dimensions are the same on Honda motorcycles with 7/8" bars but they can differ on other brands. A good pal had some risers for his SV650 Suzuki that he let me borrow and I found the dimensions differed.
In regards to ordering other handlebars, it's all about the rise and the pullback which is often a furrin lingo to most people. And the "other bars" won't be drilled for the locating pins used on Honda controls. In my opinion, using bar risers is the easy way around this problem.
I used Rox 2" risers, but the cables and brake hose really need to be lengthened. The NT has odd-shape bars that are narrow in the center and have sharpish curves to fit the space. None of the various taller and/or wider bars I have around here fit right.
I just installed some Rox 2" risers and the difference is wonderful. Much less stress on my hands/wrists. Clutch cable needs lengthened for sure but throttle & brake cables seem OK (for now anyways). However, I think I still need more setback. Just a little bit more...