need excuses to buy SN or to ask someone about where to buy SN

[Nightmare]

i have searched too much for sources in my country, found none so far so i have to resort into asking people especially my former chemistry teacher but i need an efficient excuse to ask people of where i can buy it from and possibly use that excuse to buy it from the place they tell me if i get lucky in that, i have flipped off the internet and didn't find excuses but... cyanide poisoning? shit excuse for obvious reasons, making a test at preserving meat? i did not find information of how to use it individually it seems to be used just in factories and cant find a home usage possibility so that doesn't seem like a good excuse... the excuse is also important because in the end its a poison that i can use to kill someone too so i must be careful
aside from the excuse does anybody know where do i have to go to buy it? cant order online i live in third world country and didnt find any information from the internet and didnt also find answers from this forum or the megathread about what i want to know

 

[lizardsoup]

I've seen people say you can use SN to distinguish red vs white oak

 

[GoodPersonEffed]

Used for curing shrimp, prawns, and salmon eggs, non-industrial, sold to individuals for this purpose.