Sections of Item-Specific Info on a Purchase Order

Long story short, we need an editable section for info on a purchase order that carries over from the product details page. It would essentially be another field like the “Supplier Sku” field, mixed with the “Comments” field that's on a purchase order, because we wouldn't want the Suppliers to see the field. You can pre-write info into it on the product details page, and then when you add that item to a purchase order, that field carries over with it. We need this because we have a long list of products that we want to ensure aren't ordered again as stock, but we keep them in the system so they can still be ordered by our Ecommerce customers. We would be able to easily tag those items as “Do Not Reorder”, etc. The other features available (below) don't really help solve this issue. 
-Removing from Smart Reorder suggestions, which is not impactful enough on its own 
-Adding a custom attribute tag, which is also not impactful enough on its own 
-Setting up Automated Notifications (ex: notify us through email if an item with a tag or something has been ordered), which doesn't work because it's too slow and we don't want them to be ordered in the first place 
-Removing all Suppliers, which again doesn't really work and creates more work when we would have to order one of those items.

This field could also be used to save the case count of items. In the Edit Arena of Foresight, you can input the case counts for items for when it's suggested to order, but the quantity you actually want to reorder is typically not the exact quantity. So most of the time you're going to have to adjust the “case count” that it suggested, and at that point it's pointless to have the case count only entered in Foresight. You can also put in the case count in the product details page, but we have a plethora of items that have multiple vendors, and most vendors do not have the same case counts.