Yes there are dozens at Citi Sadar Road, Rawalpindi but I would only recommend a handful of them especially for a new comer.
Myself and Akif Janjua work with Jamil Awan (first shop on the right when you enter the jeep market). He is reportedly expensive but arguably the best, especially with CJs...
Nikku Ustad is another master jeep-builder, although a lathe machine guy and alteration expert, he has a full team and can build almost anything with finesse...
Gulzar Ustad (big covered workshop on the left in the jeep market) runs a one stop shop but primarily is an FJ40 expert par excellence. Makes some of the best FJ40 restorations I have come across...
There is one chap right at the end of the jeep street who built Blakop's Wrangler (don't know his name) and then there are also some guys who run a press and churn out some excellent stuff....