Back In Stock Notifier

Does anyone have experience implementing a restock notifier in FluentCart? I’m looking to add an email capture field directly on product page when an item is out of stock (ideally positioned next to the disabled "Not Available" button) so people do not have to scroll down to find the field.

My goal is to have a simple way to collect a waiting list and tag customers with something like [productX_waiting] upon signup so I can trigger custom notification workflows manually.