For the extraction of WHAT? We don't read minds here... If you are looking for a source of NaOH, that stuff ain't it. Drain "maintainers" are mixtures of enzymes and bacteria that eat the crap in your pipes to keep them clean. The products that might contain NaOH (read the label!) would be drain OPENERS.
Given that he used the word "extraction" meth making seems unlikely. The stuff you probably want is Red Devil LYE.
NaOH is used for far more than just meth..... from soap to loratadine (Claritin). Red Devil was taken off the market, look for roebic
You might just try typing in "Sodium Hydroxide" on E-bay and you'll be amazed at how many people are out there "making soap"... This IS if you can't find the Roebic at your local Lowes or Home Depot... They also sell "potassium Hydroxide" as well, and methanol, and ethanol.... and......(you get the point) BEN dOVER