FWIW you can buy tonic syrup, just check and make sure it includes Quinine as some are mislabeled. Fun part of this story is that Quinine was regulated from being supplied "for the troops" during a war time. They just kind of slip those things through, that's how it always works.... I suppose I will dig up my evidence of this statement so I hope someone appreciates it. Seriously that just took me 5 minutes I hope someone bothers to click, on pc the key word Quinine will be highlited but on moble you'll probably end up having to read through a bunch of text from 1945

library of congress refrence