Zoroaster = Sh au ra + usta + ar = Shuara + Usta + Agent Noun = Sun/Solar Principle Rising Agent.
Another way to parse the word:
Zoroaster = jar + uuST = Withered/Aged/Old Camel.
Western Scholars are not usually trained in the rules of Sanskrit, Ancient Greek or Proto Indo European. They usually do not have the concept of "uu" or "big U" sound, and hence fallen for the Old Camel meaning.
First of all not all Truth can be established as the only one version of Truths.
In ancient times, Gujraat was connected with Iran by land. The ancient name of Gujrat was S(h)aurasthra (
http://en.wikipedia.org/wiki/Saurashtra_State).
It is well know fact that "s" and "sh" sound get confused.
Persians and Vedic people were one and around 10,000 BC they split over Iconic or Idol Worship -.or Polytheism, though Vedic people acknowledge One God Many Expressions. But they were still intermingling in important functions. This is based on some Bengali Academician who I have to search for now but recall reading this. It could explain one reason why Parsis from Persian settled in Gujrat because they felt comfortable and had some knowledge of people from Saurashtra.
Something related to Sun, is Saurya with next graded vowel sound. And Shaurya is bravery. Saurya is conencted with Golden, Brilliance, Intellect, Wisdon and even Courage.
From Wiki (
http://en.wikipedia.org/wiki/Zoroaster)
A folk etymology of the name is from zaraϑa, "golden", and the *uštra, "light" (from the root uš, "to shine").
The image of him is connected with the image of Winged Sun.
Zoroaster:
http://en.wikipedia.org/wiki/Zoroaster...Winged Sun:
http://en.wikipedia.org/wiki/Winged_sunIt says "The symbol evolved into the Faravahar (the "visual aspect of Ahura Mazda") in Zoroastrian Persia."
The connection between Jew Yeshu or Yehuwa, English Jesus, Sanskrit Ishaa and Persian Izaa is already shown.
http://en.wikipedia.org/wiki/Avesta#The_YasnaIt shows "s", "z" are connected and can be confused with "jN", as seen here: "The Yasna (from yazišn "worship, oblations", cognate with Sanskrit yajña), is the primary liturgical collection, named after the ceremony at which it is recited".
The Gujrathi/Saurasthra Script based Translation of Yasna/Yazna may have corrected the word to Vedic yajña, and this may have been the basis to take "z" as "j".
Again the words had usual two meanings, one for the common folks and one for the erudite