Try Khalid Scientific, 2nd Floor over Sports Corner by Jaidah Flyover, or Intermodal Supplies, grey austere buildings near VIP roundabout, building #5 I think.
You might be lucky if they have it in stock otherwise it will probably cost as much, or more, as you importing it yourself. On the other hand, importing chemicals can be a bit of a hassle for an individual. Discuss it with your Mandoop (Mr.Fixit).