Speaker for McIntosh setup

"Note: The system is in a large great room."

My advice would be to make sure you get speakers that are large enough. I have heard great speakers sound not good because they were in rooms too large for them. You lose bass and without the low end it sounds off. This was in a double story great room. You may end up needing a sub so consider that in the budget.

I run Focal with my McIntosh and love it.

I've been happy with Sonus faber speakers - and at $5k the Sonneto V is right in your price range.

McIntosh is better paired with neutral/fast sounding rather than warm/slow speakers. So, B&W, Dynaudio, Focal, Raidho, etc will be generally good matches.  

Surprised that no one has mentioned Martin Logan.

Despite what others may say I have never care much for B&W, Sonus Faber, or Focal on McIntosh and I am surprised there are so many enthusiastic supporters of those combos....

Used to own a pair of Vantages, the current equivalent around $5k would be first on my list.

The users recommending Klipsch are on the right track as well, especially given the vintage of the OP's gear.

But for $5K you could probably find a used pair of Summit X's or something like that and be doing pretty well. The separate powered/active sub eliminates having to worry about the otherwise "wooly" sounding bass Mac has, so the amps are just handling the mid and upper frequencies.

McIntosh XR100