I'd suggest a minimum of 400 Watts into 2 Ohms, and depending on your room and desired listening levels, twice or more than that might be more appropriate.
I think you'll find that many of even the more respected manufacturers integrated amps are incapable of doubling down and down again into 2 Ohm loads.
https://www.stereophile.com/content/thiel-cs37-loudspeaker-specifications
https://www.stereophile.com/content/thiel-cs37-loudspeaker-measurements