I've thought about selling my code snippet for handling payments on something like Gumroad or similar. However, it's not a great solution since people still need to sign up somewhere and then install add-on. Plus they need to subscribe on stripe with their same email that the add-on will use (since the code grabs their email programmatically). As I'm thinking through this, there could be ways to mitigate some of these issues but who knows!

There is someone that built something similar but for browser extensions (https://extensionpay.com/).