I got mine at SportChalet during a summer deal, 50% off. $150 for the 09/10 CTX. Love them so far. K2 hardware (screws and washers) kinda sucks, but I took the bindings off every time after riding, to wax the board. Other than that I love those bindings. Being able to use both function is great on the lift to release a bit of the pressure on your boot, and if you need to unstrap after you got stuck in the deep.
The GNU ones were great too...with an additional buckle to loosen up the binding for the lift ride. But I could not find them.
2015/16 -9- Kirkwood days
Arbor A-Frame 158 2009-10
Jeremy Jones Hovercraft 156, 2011/12
Subaru WRX 06