In the library last Friday, I also scanned through Zoroastrianism: An Introduction by Jenny Rose. I have been interested in the history of pre-Islamic persia, especially the "Achaemenid" Empire, but was not able to find much information about this. The only books I recalled on Zoroastrianism are books from several decades ago by Mary Boyce.
As related to the world canon, whether any Zoroastrian work should be included is a question. On the "plus" side, it is old, possibly antecedent and had influence on Judaism which subsequently influences Christianity and Islam; it is one of the very few traditions for which we have texts of in the pre-Islamic Middle East. One the "negative" side, its current adherents are small (and so does Judaism), and in a way it's foundational texts (Gathas) has some similarity with the Rg Veda.
In any case, as I flip through Rose's book, I think that if any text from Zoroastrianism is to be included, it is most likely going to be the Yasha from the Avestan scriptures, which includes the oldest Gathas, plus some "Young Avestan") materials.