its basically a pad hack, so you would need:
-an old stick (i had an old TE lying around with a broken pcb, I just gutted all the wiring inside.)
-xbone controller (taking the stick, buttons and cover off and using the board as the new pcb)
-mini usb cable (I also picked up a usb extension cable for some extra length)
theres lots of soldering involved, so its something you can only really do if your confident with it.
So yea, you'd have to weigh up the options and price, it would be about $300~ to pad hack, or you could buy a KI stick and hv it shipped to you (approx $350~)
def a big investment, games worth it

(im pretty biased though)