The boundaries are similar (though not exactly same) as the ones depicted in Joseph E. Schwartzberg's A Historical Atlas of South Asia (1992), Plate XIV.2 (page 146) [1]
作者
Ἀλέξανδρος ὁ Μέγας
The file is derived from a previous version (on 5 January 2012) of File:Karkota Empire, India.jpg created by User:Ἀλέξανδρος ὁ Μέγας
The above image depicts the map of the Karkota empire in 8th century CE. It is clearly depicted the empire ranged from Kabul (Afghanistan) in the west, to Arunachal Pradesh (India) in the east, covering the whole south of the Himalyan mountain range.