You can bet people who use it regularly stockpiled the stuff. Of
  course you'll still be able to find it, but it'll be in the
  "back room". You can ALWAYS find poison of any kind that 'used
  to" be available. Just have to ask the right people the right
  way. we don't use poison but I remember my grandmother was a pro
  with that stuff. She was like a household scientist [for a
  seemingly emotionless woman, she also had a crush on Spock I
  think; and adored Engineers generally... and believed in ancient
  Aliens but only a little.. and in secret Tesla documents...
  anyway..]

  She'd come home with some stuff for the garden that was banne d.
  A city girl, she knew how to talk to the garden shop owner to
  get stuff she wasn't supposed to, 'cause, well, the stuff
  worked.

  She also managed to get a hold of Dr. Brown's Cough Syrup long
  after it was banned because she knew how to talk to the
  pharmacist. [I wasn't alive yet - these are stories I heard].
  Funny thing, she wasn't a flirt, but she was smart and I think
  she knew how to impress the shopkeeps... who, were probably
  flirting with her, Wait.. could she have been flirting? O_O
  [1]#childhoodruined

References

  Visible links
  1. https://www.facebook.com/hashtag/childhoodruined?hc_location=ufi