Try to get a double channel ( 02 nalli) kabli one (ranges bw 6500-8000) single nali wala would be a bit cheaper than this.
U can also get qoutes / advices from Kaalia Ustaad, one the most renowned guy for Radiators in RWP (Chah Sultan). HE got so many in stocks. Here is the details of his nos.
If he didn;t ahve any then contact Raaz Khan @ 0300-9553066 (give my reference, ask him Adeel nain bhaija hay) & he'll get one for you in comparatively good price.