Do yourself a favor, and stop watching those videos. That will change the profile and geometry of your knife in a way that it was never intended, unless you are sharpening a mezzaluna.
There is no "western stroke". It's an idiotic, ethnocentric extension of the idea that the "East" is some place filled with dragon smoke and gong noises and knives behave differently there. What is commonplace is different depending on where you go, but sharpening a knife is the same no matter where you are. Mark has a series of videos on CKTG about sharpening, and if you want a succinct rundown without any kind of nonsense in it, surprisingly enough, there is this video:
That "EZcooking" guy is on the short list of nutty people that made me start making Youtube videos about knife stuff. He talked into a camera for 45 minutes to explain how to use a honing rod.
These round stones from Naniwa as well as the large rectangular stones are available from Naniwa. I've seen them but for the price I really don't think they are particularly useful. The formulation of these stones most closely resembles the Naniwa Superstones. I would prefer Choceras over Superstones if this is what you are interested in.
Also consider that flattening these stones would ideally require a LARGE flattening stone. Naniwa does make one 150 mm x 300 mm in 24 grit, but to be kind, it really is not a very useful stone.
Consider using standard sized stones instead. They are more than large enough to meet your needs, even if you are sharpening swords or machetes