you can get some cheap ones and see if it would last long or stick to a known brand like philips, osram etc.....but either way, u will still get the error message. so you'll need to compensate for the bulb resistance.
there are few ways to skin a cat, i went and bought a reasonably cheap xenon kit (approx $200 AUD), ran a feed supply from battery to relays which switches the xenons. i had to fool the system by wiring in a resistor each side - 50Watts (which is fairly big!), had the xenons for almost a year now. no probs yet (touch wood )

i still regret not ticking the xenon option when i purchased the car. oh well

i think u should stick to 6000K. youll be surprised how blue they are