Your lights are not xenons mate, the mk2 ph1's did not come with xenons, only the mk2 ph2.
Your lights are projector lights and can be fitted with aftermarket xenons but this involves buying and installing xenon ballasts.
SO, assuming you have not fitted aftermarket xenons (you'd be able to see the ballast boxes) then you just need a standard bulb to fit.
Whether you choose ulta white ones or whatever is up to you