misophist,

looking up Rustum and Sorhab you should use the scientific transliteration Rustam wa-Surhab. That is one of the books I found:
Firdausi [Dastan-i Rustam wa Suhrab az Sahnama] Dastan-i Rustam wa Suhrab az Sahnama-i Firdausi : ba tagdid-i nazar dar tashih wa taudih-i matn wa muqabala ba nusha-i Flurans / muqaddama wa tashih wa taudih-i Mugtaba Minuwi. - Cap 2.
Tihran : Mu´assasa-i Mutala´at wa Tahqiqat-i Farhangi, 1990 = 1369 h. s.. - 3, 19, 415 S.; (pers.)
(Mu´assasa-i Mutala´at wa Tahqiqat-i Farhangi ; 627)
Original: Sahnama
Nebent.: The story of Rustam va Suhrab from the Shahnamah
Teilausg. v Sahnama. - In arab. Schr., pers.
- - - - - - - - - - - - - - - - - - - - - - - - - -
Universitätsbibliothek Tübingen:
Signatur: 31 B 1830
This is the 2nd print.
It is a part only of Firdausi's famous Shah-nama (Book of Kings) printed very often; the newest scientific edition is published in New York in the Persian Text Series.

The Romans adopted the original names of countries and peoples transforming them often to their usual pronouncings. So Persia seems to be derived from Pars (there are Parsi communities in India; they had to leave as non-Muslims some centuries ago). Since the true Arabs don't have "P" in their language and script, they transformed Parsi into Farsi. The name of the language Farsi is very old; the name for the state was adopted by the new Pahlawi Shahs having reigned from 1925 to 1979.

Lepus Rex,

The Aryans are not Indo-Iranians, but members of the great Indo-European language family. This name was chosen from the Eastern and Western borders of the range. In former times it was called Indo-German, but this excluded the more Western Roman languages, so the name was changed.
I have met a lot of Iranian racists who were proud to be Aryans from a "better" or "higher" race; I used to stop them by a racist answer from the European view which is not printable here.

Wilfried