Another option would be to break apart a wired Rock Band drum kit so it's just the center controller and the drum pad the USB cable comes out of, connect that t

Another option would be to break apart a wired Rock Band drum kit so it's just the center controller and the drum pad the USB cable comes out of, connect that to a computer and use Joy2Key (or an equivalent) to map the bass pedal to Esc/i. Not nearly as nice, mind you, but if you're sitting on a half-broken kit like I am, it is cheaper.