I don't think I've ever seen a grafted succulent here in the US. They probably exist, but they're not common if they are. Always a bit jealous to see when you post a new one.
Some types are pretty popular here in Japan and available everywhere (like those red or yellow cacti that don'treally grow well in soil), but this is the first time in saw a graft like this too. Not even sure how exactly it works inside to be honest :)