Keep in mind that this is just my opinion.
I do not think we need to stock up on anything other than mods,tanks,and nicotine.The only flavors i see having a problem getting may be tobacco type flavors,and those made specifically for vaping.Tfa,Capella,etc. are all food flavors that were not made for vaping.18650 batteries were not designed for mods,they are used in a lot of rechargeable tools,flashlights,laptop battery packs,etc. Cotton or rayon were not made for vaping,and Kanthal,SS,and nickel wire were all not designed for vaping.
All of these things were around long before vaping,and all are used in several other applications that the Fda has absolutely no control over.The flavors,yes they can control those,but again,they are food flavors for food use,we vapers have figured out that they can be used for our purpose,but that is not what they were designed or intended for,except like i mentioned tobacco flavors,and most of the dx/v2 stuff.
Trying to stock pile batteries will eventually leave you with a bunch of bad batteries,as they have a shelf life like most everything else.