My guess is that you'll never find one. Reason being that everthing you've mentioned is a function of the phone itself not the handset, the headset wireless or wired simply extends the handset.
Now you might be able to mix a single line wireless headset / phone with the 2xxx and get something to work... or find one of those discontinued cordless 2616s
Or maybe there is such an thing but I can't figure out how it would work on a digital phone simply by extending the handset.
