Checking GoPro.com for lenses.

They've shifted to selling authorized 3rd party lenses from polar pro. You can get them on the polar pro website, amazon, or direct from GoPro.

• https://gopro.com/en/us/shop/mounts-accessories/polarpro-red-filter-hero8-black-protective-housing/APPRO-002.html
• https://gopro.com/en/us/shop/mounts-accessories/polarpro-divemaster-filter-kit-hero8-black-protective-housing/APPRO-003.html

• https://www.amazon.com/PolarPro-DiveMaster-Filter-Protective-Housing/dp/B07XZQ22PT/

• https://www.polarprofilters.com/collections/filters?_=pf&pf_t_action_cam=ActionCam%3AGoPro%20HERO8