SAR reader Stefan noticed that:
Dirt cheap: $300 for housing + add ons. package is $1000, usually $3k upwards
https://meikon.com.hk/collections/underwater-waterproof-camera-housing-case-for-sony-camera/products/sony-a7-ii-40m-130ft-underwater-camera-housing-kit-with-dry-dome-port
Meike stuff is usually availabe on Amazon US, Amazon DE, Amazon UK and on [shoplink 60751 ebay]eBay[/shoplink].