Anyone know of a temperature display like this?

The Antec Flux Pro case has this display on the outside. I was looking for an add on like it but everything I see are hugely complicated and expensive. Anyone know of a simple and inexpensive one?

https://preview.redd.it/ytbp3g50mzce1.png?width=640&format=png&auto=webp&s=524529d218524e42335639a668cbbe2f28734ab1