Access cart line_item.final_price before the item is actually added to cart

Before doing anything hacky, I’d like to know if someone has some idea on how to tackle this.

The idea is simple: I want to get the line_item.final_price of an item as if it was added to cart, but it actually is not (it’s an upsell). This item might trigger an automatic discount, and therefore be discounted.

So, if adding this item will trigger the automatic discount, I want to display its discounted price, otherwise standard price. This is in the storefront, not an application.