I have given very serious thought to doing just that. Aside from paintball, my buddies and I hunt a lot. We have radios to keep track of our locations that have range of up to 300 yards over rough terrain. Basically very good. They even have a head set. On top of that we tinker and have been trying to solve this problem.
As you were implying the problem is that the headsets will not fit into the mask. If you don't mind doing some serious work it can be done. You need to strip the headset down to the bare-bones. Just get the mike, wires, and speaker. NOTE: I HAVE YET TO DO THIS MYSELF SO DO AT YOUR OWN RISK. Then you should be able to mount it all in its proper place after insulating the wires with electrical tape. When I get the money I plan on doing this and I will post better directions that are further than the drawing board.
If all goes the way I have it planned I should have a great mask with microphone and (now) a nice air system.
Must it take a life for hateful eyes to glisten once again?
And we find ourselves in the same old mess singing drunken lullabies...