Since I sell (and enjoy drinking) adult beverages in central Texas, I find this kind of article quite fascinating. If you make another post just about cocui, I would appreciate and upvote that. The same also applies to the rums and beer you wrote about here!

Do you know if any of these drinks are sold in Texas? Especially cocui?

Using Google, I found only one article, which mentioned that some agave liquors besides tequila are available at an Austin bar called Qui. The article, from 2015, didn't say if cocuy was one of the liquors being sold there.

https://www.eater.com/2015/3/4/8126129/beyond-tequila-alternative-agave-spirits-to-know

Unfortunately, Qui since then has been closed.