You might stock up on genuine stuff that will become available aftermarket if it is not already. 2 months is my wait time and that is for two items waiting for the second one to come in before shipping. I can see stocking up on parts for discontinued models that will become nla eventually. Still, what is the cost of a new replacement saw? Are you a collector or someone that looks like it is something to depreciate to zero and then it owes you nothing so to say. You going to buy a coil in case yours goes bad? Your post is kind of vague about your particular situation.
The mood on here seems to be that Stihl stuff is real expensive but for me a sprocket for a pole saw or a gearbox for a 35 to 40cc string trimmer/brush cutter Stihl is less money and just a fat week from a local dealer.