Adding already existing items into a loot table

Making tons of items was fun and all until I got to know that some of them should be found only in structures. Both structures - vanilla and datapacked in. Sure, making a loot table is easy but it requires me to make an item INSIDE of the loot table. I have over 60 items that I have to add into a loot table, and re-making them in the function file isn't quite quick. Names, descriptions, and etc - I will have to re-do all of it. Is there any way to add already existing items into a fresh loot table?