(self-edited)
why dont you try
1) Hyndai Sowan Motors (near Sowan Adda Rawalpindi)
2) auto shops in Azhar Shaheed Market (near Kamran Market Saddar RWP)
Though chances of finding GV cylinders are slim but if you find them...nothing like that. Other than Hyundai Santro, no hatchback in Pakistan has that kind of CNG cylinder system as per my limited knowledge. Each cylinder is 14 kg approx (42 kg total). See how concealed their placement is, leaving much needed boot space empty. Amazing
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