Tourist visa to visit Kashgar via Khunjrab Pass.

We are a group of 6 friends from Pakistan and want one week tour of Kashgar by road via Khunjrab pass Karakoram highway. please let me know what type of services you can provide and what will be your charges. Also if I want only invitation letter services from you and rest tour we plan it our self. I mean accomodation, transport etc will be arranged by our self just for the sake of getting visa we want ur services. in that case how much you will charge. We are low in budget and need ur kind co operation in this regard.

Thanks,