CASIO SA-10 (DEMO song) - Wham! - Wake Me Up Before You Go-Go - YouTube
Running with you - Casio Cz-1 demo song (see in comments) : r/synthesizers
Casio CTK-495 Keyboard 100 Demonstration Songs Part 1/5 Songs 001 to 021 - YouTube
Amazon.com: AODSK Keyboard Piano for Beginners Electric Keyboard 61Key With LCD Display Kit for Professional,255 Sounds,Microphone,3.5mm Jack and 24 Demo Songs : Musical Instruments