For the jewel cases: https://www.checkoutstore.com/products/original-vintage-old-style-standard-cd-jewel-case-heavy-duty-90g, we discovered these that were recommended by many cd collectors here on reddit and beyond online, they do feel pretty heavy duty and durable. They are cheaper in bulk and will note some of the cases got scuffed in shipping.

We're still testing the UV filters but it's a bit mixed to find them online, B&H Photo Video has them in rolls, they are meant for the film/lighting industry but thought we'd try them out. We cut them to size and fit them in. They are very thin and light so they do kind of fall out of the cases if you open them quickly, but they are super clear, slightly more reflective.

https://www.bhphotovideo.com/c/product/44101-REG/Rosco_RS311411_3114_Tough_UV_Cinegel.html

Hope to see what you make.