I'd check out Delta. For PIT>FCO/FLR>PIT, I found a BUNCH of availability for an 10-12 day trip for 2 travelers in Aug/Sep. See below:
I'd recommend booking these Delta award flights via AeroMexico Club Premier (SkyTeam partner). Each USA>Europe SkyTeam RT economy ticket booked via Club Premier is 80k Club Premier Kilometers (KmP). There is currently a 20% transfer bonus from MR to AeroMexico Club Premier
Miles, which convert at 1.6x to Club Premier Kilometers (aka KmP-- I'm being serious). Thus, you'll need to transfer 84k MR points to receive 161,280 KmP.
85k MR x 20% transfer bonus = 100,800 Club Premier Miles
100,800 Club Premier Miles x 1.6 metric conversion = 161,280 Club Premier Kilometers (KmP)
You'll have to pay the taxes, fees, as well.
Using 84k MR for to fly two people to Italy seems like a great value to me! You can fly biz class with similar availability (from 8/20 to 9/1), but you'll have to fly back from FCO, or NAP, not FLR. Best of luck!
ps-- I just looked up the cost of the flights I saw. You'd have to pay $3,662.40 cash to book these flights (PIT-CDG-FCO/FHR-CDG-PIT). You'll be getting 4.4 cents/points value out of your MR points! Excellent redemption!