Normally I would say Naim but their integrated (Supernait 3) may not be high enough end for what you are looking for. The Uniti Nova would be a good choice if you are looking for an all-in-one. Naim and Focal are same company and focal is voiced using Naim amps.
There are tons of integrated's that will do the job though.
I would look at the AVM OvationA6.2ME. It has plenty of power, can handle the low impedance and Herb Reichert gave it a great review a few months ago and Stereophile gives this unit and A rating. It is warm and sweet. You will get nice tight bass as this will not struggle to drive them which can be an issue with some tube amps.
I have used the 5.2 integrated with Sopra 1s, Vivid Kaya 45s, Perlisten S4bs and a variety of other low impedance speakers and it matches well. The 6.2ME is just more refined as it is AB with a MOSFET output stage rather than Class D with a tube input stage.
There are a million others. Mark Levinson, Boulder, Aesthetix, Luxman, Sugden, Pass, Rogue, etc... Everyone is going to have their favorites. All will do well with small differences in flavor. I am biased in favor of SS/Hybrid Class D with Focal due to the lower impedance requirements.
Full disclosure, I am a dealer for Naim, AVM and Hegel but there are obviously lots of other dealers. Good luck.