>>1054928there are also strap on pads like this pic related that you can just pull over. but donno how good they are that might be easier with the pack you posted.
German page as example: 14€
https://www.amazon.de/Hazard-Taschenzubeh%C3%B6r-Single-Shoulder-ACS-SPAD-CYT/dp/B00889AVOA