He seems to sell them via Tencent QQ secretly. That's probably his account ID(like the equivalent of paypal address)that you send money to directly via the app and then he sends you the files. Tencent QQ is a Chinese state run general communication, banking, commerce, social media etc. app. It's their largest app by far with like 600+ million active Chinese users and is basically their equivalent of Twitter+paypal+banking+debit all-in-one.

Unfortunately they don't accept foreign credit cards unless you use loopholes and even then it would probably be a big pain in the ass to try and find a way to sign up for the app. Hopefully he decides to sell them on hiccears or another China friendly site at some point.