Limitation of shared articles

Right now there are two options for shared articles: to give access for all external users without any subscription OR to limit each shared article up to the first paragraphs.

We would like to introduce the opportunity to enable paid-users to share articles completely, but each of them should be limited up to a fix number of users. At the same time, we want to stop misuse of our paid-content from users without any subscriptions i.e. via social media etc.