Kodachrome is widely available, but not everywhere advertises it on the internet.
Stop kidding yourself, Kodachrome is not widely available at all, it's been withdrawn from sale in most countries other than the US, although there is still film available in some stores. Sending film to Dwaynes is not that attractive if your outside the US when E6 processing is readily available and faster & more convenient.
Kodak seem to be withdrawing Kodachrome, once their flagship colour film, gracefully without an abrupt halt, unlike they did with B&W papers. It does seem that we constantly re-hash the death of Kodachrome but Kodak started its wind down a few years ago, and it appears to be unstoppable.
Much of the current serious film user market is slowly moving away from 35mm, and 120 and particularly large format are becoming more popular Kodachrome never really took off in those markets. Kodachrome sheet film disappeared very early, and 120 Kodachrome never really took off because of the slow turnaround of the processing.
I guess it also doesn't help that Kodak discontinued K25 which was the jewel of the Kodachrome range, if the K-14 process had been more freely available world-wide then things might have been very different. I think there was one independent K-14 line in a London lab for a short time but it came too late, everyone had switched to Fuji 50D & E6 to get similar qualities.
Yes remaining stocks of Kodachrome will be around for a while, and Kodak may still have some left from the last master roll to confection, but it's not a mainstream product any more , none of my suppliers don't sell it any longer. I could still buy it if I really wanted to, but as I never liked K64 it's too late, there's no new K25
Ian