Couple folks have done group buy batches, @DEEIF@kevingraehl , in the last year. FullSend/@Skyart sell them and @Tony_Stark has some heavily custom ones coming soon.
I believe you can buy them straight from their alibaba store as well, but most likely without the custom specs unless they’ve adopted them to their stock motors.
They’re not good without a pretty substantial list of mods too, so you’ll have to buy one from a good batch ordered by one of the people mentioned. IMO, flipsky motors are going to be the best choice 99% of the time. Even if you want the highest reliability, you’re only getting marginal gains spending double the money