Jeff, I feel somewhat qualified to answer as I have owned a mac 7100, and I am a fellow Jeff. I actually miss the punchy lively sound of my old 7100, I ran it with a ARC LS1 and into some Thiel 2.2s, I have fond memories of that system. Anyway that was long ago, I am a huge fan of Wyred4 sound. One of their 250 watt amps will likely get the job done. What preamp are you running?
Thx Jeff