These are the same red ones that come in the Super Mario Odyssey bundle. They're actually RED red, not that weird neon red, and I like these much better. They're only sold separately in Japan, so as of right now(December 4, 2017), the only way to get them is by importing them.
Edit: As of September 29, 2019 I now have had 3 of these fail due to buttons dying or sticks drifting. 3 out of 4.