Boundless Chest Symbol of Below  

You can see, purchase and scribe these books with less than 300 skill. For every other skill limited recipes, you cannot even see the books on the vendors until you have a minimum skill. Unless someone actually attempts the recipes to confirm, I would go with the assumption that these do not have a minimum skill required. When I attempt this recipe with my level 52 halfling with a tailoring skill of 133, I'm just told I don't have the ingredients, not that I'm not of the right skill to make the item.