Another option: Sibelius by Pearl Acoustics. I have not heard them. They have reviews on the web, though. Just received via email from Harley at Pearl Acoustics (owner and maker of the Sibelius line): "I can absolutely assure you that the impedance of our drivers, in their enclosures is a true nominal 7,5ohms. The lowest it goes is about 7ohm at around 5hz. It rises and drops sharply around the resonant frequency at 38hz. And rises up to about 16ohm at around 20KHz. But there is absolutely nothing to worry about here. The Sibelius is easy to drive and very forgiving for the amplifier, from this perspective.”
https://pearlacoustics.com/sibelius-sg/