Backing track can be found here: https://freesound.org/people/danlucaz/sounds/499594/
I changed the pitch on the original backing track by -4 semitones IIRC.
Please contact me if you would like to use this in a project. We can discuss the details.
* Contains third-party samples.
Excercise caution when using it, refer to author comments / contact the author for details.