There are about 4 shops near waseem autos in Rawalpindi, I saw them there.
I visited there and asked for the Xanadu brand and they said, they don't have it.
The next day (last Sunday), I visited them again and asked for the road head lights for Suzuki 150, the guy at waseem autos shows me 3 head lights and one of them indeed was xanadu but without box so I wasn't certain if it is original (I cross checked with the pics whose link you have posted).
He asking was Rs. 900 for it.
What I learnt in the past couple of weeks is that many shop keepers don't know the brands so you got to get them to show everything they have got and then filter out the item based on your knowledge.
A friend also recommend a few shops in saddar pindi and a dealer in F-10, Islamabad. Gonna pay them a visit tomorrow.
Hope, this helps.