Calmex in Fallout London

As part of one of the side quests, you will receive a task related to finding the drug Calmex. You need three doses, and the NPCs hint that you can find several dealers in the area. Having searched almost the entire location up and down, I did not find a single dealer. I also failed to find Calmex either in buildings or outside.

Instead, I offer you a simple solution: open the console and enter the command player.additem 00058AA7 3.