>>380000791
Sorry to tell you, but there really isn't anything viable and readily available right now that's not vive trackers. Beware of shills offering alternatives. It's possible there may be some in the future, but not right now. Even the tundras that were anticipated for so long costs just as much as vive and also comes with its own set of problems.
If you've got a kinect already you might as well set it up since there's nothing to lose.
If you're going to buy kinect just for VR FBT, that's probably not the best financial choice you'll be making.