A combination of the products that we provide would be used to create a paid for site. You would need to use Security Assist to limit the access of pages for users. Each user would have to log in to use the page. Using SecurityAssist, you would be able to set several levels of access to the pages. Some that you don't need to log in to see, some that you have to be logged in to see and some that you have to have paid for the access to. You can then use eCart to charge the user for access to the site. After the user has paid for the access to the site, you will give the user access to the page(s) that they have paid for.
We do not offer a prebuilt solution for this kind of thing, but using the tools could be helpful to create the site you are looking for.