Can Premium Membership be used to offer a 'pay as you go' option?

I have just purchased membership and would like to know, is it possible to allow users to pay for access to a single post (without having to create a seperate subscription for each individual post)?

My goal is to have a site that offers a free sign-up, which charges you per article to read. Or a subscription that gives you access to everything while your subscription is active.

Thanks,
Kev