Found a video that confirms this: https://invidio.us/watch?v=YgBOLLgMEio&t=421 (quite a fascinating museological experience in itself).
Thank you so much for satisfying a long standing curiosity and a salute to your formidable Googling skills!
Likewise, thanks to you! Actually, this book uses almost the same image, but clearly the designer or someone else couldn’t bear to have a representation of the Buddha without a bobbly thing on his head so added one. When Googling myself, I saw a number of these image adaptions.
Lastly, another thanks to @SCMatt for the Invidious recommendation (in the other thread); YouTube has become increasingly unbearable.