For GTI lights you'd get them from Mydepots as well, but instead of H4, you would need the H1 fitment. I checked Ebay last night and there are a lot of people selling them on there pretty cheap these days so can probably get them from there as well. The kit looks exacly like the one I got. Its just that when I went to but them for the valver a year ago, the cheapest you could get them on Ebay was £120, now they seem to sell them for £50,lol.
Last thing to check if you have H4 bulbs is if you require bi-xenon (high and low beam built into one bulb) or if your headlamp uses two bulbs (one for low, and the other [or both]) for high beam). The Bi-xenon bulbs tend to cost about £20 more.
Mig