NAD M33 and which speakers?

Start with whatever Harbeth you can afford and take it from there...

I have a pair of the Amphion 7LS and I am running them off a similar integrated streaming amp set up and it sounds pretty incredible so I would imagine the Argon 3S would work excellently as well!

I use my M33 with Paradigm 3F floor speakers. Love the sound.  I haven’t heard the Persona B stand speakers, but I would certainly give them a listen.  Paradigm Persona high end speakers are beautifully constructed with choice of several colours and produce beautiful sound.  Made in Canada with not a huge share of the American market.  Selling them in Canada, they move very quickly.  Good Luck.

I have them hooked up to KEF LS50 Metas. 

I used Monitor Audio Gold 100’s and they were amazing in my small bedroom setup.