Without research, a brief history of spell crafting. The very first spells were crafted from "words", "writs", and "runes". Only casters could make them and no one could make tomes. A big change eliminated all those items as components for spells. Instead animal skins were used for lower spells and various forms of papers were used for middle and higher level spells. The last big change allowed all classes to make spells and tomes for anyone. Even today there are many early spells, tomes for which no recipe has been found, maybe not created. Is my assumption correct that this spell dropped intact as a spell?
Yes, and it was not sold in era... but there most definitely is a recipe, and based off the ingredient list, it could have been crafted in era as well.
