Walaikum Asalam brother,
In Karachi a week ago it costed Rs. 5440/-
The breakdown is:
Rgistration: 4640
Number plate: 100
6 months rd. tax: 500
CED: 200
process is simple and no agent is required unless you dont want to spend an hour yourself. Because of the new ban on applied for plates, you get official number plates in a few hours.
hope this helps.