There are two big shops just before joining M9, Shah Autos and Tariq Oil Agency, here's Google Maps link
https://maps.app.goo.gl/2dEbSZdG5v9bvaLt7
I believe they are selling legit stuff, as Shah Autos seems to have lot of Shell stock. Bought Caltex from Tariq Oil Agency last time, and experience is pretty bad.
I will share my experience for sure, as car is feeling quite noisy and makes tik tik sound for few minutes when started in morning. Rest of the day that sound is not noticed.
For my Pajero Mini 1995 660cc Turbo.