If you are open to tube amplification,
and given that the Sopra n2 are said to be a relatively easy speaker to drive,
I'd strongly recommend a Raven Audio amp. Sound stage is just through the roof, vocals are sublime, and bass is deep and tight. Since you mentioned an integrated amp, The Raven Reflection MKII comes to mind. I have heard it driving big tower speakers, and the sound was fabulous. Not to mention, this thing is drop dead gorgeous! Unless you will be trying to play rock or rap at concert levels, the Reflection should have plenty of oomph.
https://www.ravenaudio.com/Reflection-MK2-Integrated-Amplifier_p_12.html
https://www.ravenaudio.com/Reflection-MK2-Integrated-Amplifier_p_12.html