You can find them in the mucped23.zip file linked here (encoded as PNG): https://github.com/google-research/google-research/tree/mast...
Here's an original: https://gist.githubusercontent.com/simonw/5a8054f18f9ea3c560...
And the jpegli-q95- version: https://gist.githubusercontent.com/simonw/5a8054f18f9ea3c560...
And the same thing with mozjpeg-a95 https://gist.githubusercontent.com/simonw/5a8054f18f9ea3c560...