ordered him one of these, which as far as I can tell, is the best
headset on the market right now:

The 50D had the best combined passive and active noise
reduction, but it's out of production now. Perrone mesh
(snoopy) helmet is on back order.
Feels nice. Put 2 AA in, ANR works. Has Bluetooth, so he
can listen to music and talk to Siri without any wires during
the wingovers, which I guess is nice.
I'll get back to you, and let you know if it's as good as (or
better than) the 50D.
Anyone else tried one?