Ages ago (80’s I think) there was talk of making lead free solder the only type that was available to consumers, and my great uncle (a deal horder) went out and got 2 cases of radioshack 64/40 resin core. Pretty sure it’s the same stuff you can still buy today, but I’ve got another 4 spools in my kit (that are old enough to drink).
In my uncles defense sometimes his deal hording paid off. He once saved a family reunion when our venue fell through because he happened to have a dozen brand new hibachi grills in the apartment he rented just for his stuff. And he made a small fortune when he bought a bunch of freon before it went off the market.