Subscribe on categories

I am building a website that uses woocommerce. Each product added in woocommerce is related to a custom post type (business). The way products and businesses are connected is via a Custom Field – Ref.Number. I added CF Ref.Number to both Business and to Products. If this number matches, than it shows that the X product is sold by the X business.

I want to be able to subscribe to certain category of products and businesses. So whenever, a new product/business is published in certain category, a notification is sent to subscribers.

Moreover, I want to be able to subscribe to a certain business. This way, whenever that business lists new products, a notification is sent to subscribers.

Is there any plugin that does the magic!?