If you want the path to where the customer added it to the cart, you are looking for: (Line Item) Commerce Line item: Display path. If you look the default Drupal Commerce cart view, that is what is used.

Now, if you want the link to the product itself, I believe you would need to create a simple view that would accept a product id as an argument from the URL and then display the fields you want to display. I would think showing the product display (instead of simply the product) would make more sense to the customer.

Josh

I presume you have the node title of the product display node as the product name? You can create relationships to show this in the order view http://www.apsinfrastructure.co.uk/blog/drupal-commerce-cart-node-fields