Do you fully trust that guy?!?
Sorry, can't offer any tips ~ other users already shared extremely useful tips. Also, I only specialise in car accessories, soo yea ~ follow the tips of other users.
Most nimp battries are imported from japan ( used batteries ). People in pk are like " japannn da saraa kurah kad ke le aao". Some shops label em as "kabli". Some batteries are repaired & sold as " nawah " fresh mall etc etc. Manjan vechan I ne, lols !!
Point is, there's nothing like "nawah battery". All of 'em are used ones in pk. People offer warranties on them, meh ! 5 saal di guarantee, sar ji.
This is the best tip by far, if you are looking for a long term solution. Tho, I'm not sure if these parts/batteries are available for purchase in the respective dealerships. But yea know this, they will be expensive ~ if available. It's worth every penny, unless you end up getting scammed from that dealership. These dealerships specialise in removing the clothes of the buyer/user
Who knows?!? Maybe, @Xulfiqar can guide you better.