It looks like there are a few similar products designed for your problem specifically.
amazonBuy MedCline Shoulder Relief Wedge and Body Pillow System, One Size, Right or Left Side Sleeping Comfort, Medical Grade, Removable Cover: Specialty Medical Pillows - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
https://www.amazon.com/dp/B07GTB5BFB/ref=nosim?tag=cougarboard07-20[https://www.amazon.com/MedCline-Shoulder-Pressure-Side-Sleeping-Included/dp/B07GTB5BFB]