Stocking levels depend on the store, or perhaps the district. Some still stock reasonable things. Or at least try to, "supply chain shortages" are absolutely still a thing... shouldn't be with calipers much, although I occasionally see it with brake pads. Or it could just be stuff that, sorry, ain't really common anymore... maybe you think brakes for an 82 C10 are common (and they were, in '92) but if they sit on the shelf 6 months before they sell cuz there's only 30 of them in a 5-county area anymore...
But you're dead right on the website/catalog... the newest stuff they put out is absolutely horrible. No idea what they were doing, it was pretty OK until they did an update about 6 months ago, and all of the sudden now you have to be hyper-specific or you get off the wall BS, and if it doesn't list your hyper-specific search it also shows off the wall BS. They ruined Prolink the same way, as well as in-store cataloging. BTW, I have a PDF of the old farm & industrial ignition book, it's unfortunately a scan & you can't search it, but it's what I got, I'll send you a link to it in a couple days...
I'd be happy to have the PDF, thanks in advance.
Here is a link to Standard Ignition. You can still find stuff there, even for 1940s Ford N and Ferguson tractors.
https://www.smpbuyersguide.com/standard/Ignition-and-Electrical-Illustrated-Parts-Guide-2022/921/#