Valve's new high-end headset, called Index is available for pre-ordering. This unit is all by Valve (no mfg partners, so the software and the hardware are all by Valve). Here is info about it (lengthy, wonky video) by Tested:
Caveat: this is a pricey headset (~$1000), but has some unique features that might make it a good choice--budget permitting--for sim players.
FWIW,