API in JavaScript for enable/disable the "Notify me" button

We want an API in which we could enable/disable the "Notify Me" button for each product. The API should be available client-side (and NOT server-side), and in JavaScript, so we can call it whenever we want.
I'll try to make this a little clearer….we are not using the core product data to power these particular pages.
a little clearer, we are not using the core product data to power these particular pages. This means a few things:

1. We need to be able to control when the notify me displays/hides
2. We need to be able to control what data the notify me popup has when it displays as it may not be relevant to the product they suggested.
3. My hunch here, this is a JavaScript-based update.