This happens in cycles.
Moral of the story, if you are an avid and frequent shooter, always keep a THREE-YEAR supply of powder, primer and bullets.
I take it one step further. I keep a three-year supply of the primary powder I use (which happens to be Varget) and I keep a three-year supply of a second-choice that I like equally well (which happens to be TAC). There is nothing magical about Varget or TAC. There are lots of other powders equally-good, and equally-useful, for my needs. I settled on Varget and TAC because they are produced on opposite sides of the world. I figure if there is some local factor affecting the availability of one, that factor is likely not going to be in play with the other. Of course, there is always this "shortage-and-hoarding" thing happening in the U.S. Well, that's why I keep a three-year supply. I figure if six years goes by, and I still can't get gunpowder, there are likely bigger things for me to be concerned about than shortage of reloading supplies.
I understand there is the cost issue. Three-years supply of bullets/powder/primers costs some significant money. If you are starting with ZERO, you may need to work toward a suitable supply as funds allow. I've been accumulating this stuff since I was 9 years old. Fair to say, I'm caught-up on inventory.
Some folks can't stand the idea of having old powders or old bullets - I suppose on the notion that something really-better will come along, and they'll be stuck with powder and bullets that "aren't as good." That just hasn't been my experience. The manufacturers want you to buy the newest-greatest copper-fouling-remover-temperature-insensitive-supremely-consistent product. I've avoided that way of thinking, and my competition scores have not suffered.
I believe some folks fear that primers and powder will "go bad." Properly-manufactured powder, stored in a temperature-stable environment will maintain full integrity for a very long time. Moreover, if you ROTATE your stock, none of it should be very old anyhow by the time you use it.
Can't find any Varget? Time to select your alternate powder. And stock up.