Here is a site I have used to help identify Punch Marks for Ancient India Punch Mark Coins: https://indiacoinsmarks.wordpress.com/2013/11/07/punch-marks-on-ancient-indian-coins/
https://www.acsearch.info/search.html?id=1409633 MAURYAN EMPIRE. Samprati, 216-207 BC. AR Karshapana (3.22 gm). Four punchmarks / Two punchmarks. M.4196. Toned VF [Est. $150]?
I have a few of the Ancient India Punch Marks: India Maurya ser VIB AR Karshapana punchmark 270-175 BC ASHOKA India Mauryan or Sanga 3.4g Rect India Mauryan or Sanga 3
MAURYAN EMPIRE. Ashoka, 273-232 BC. AR Karshapana (3.03 gm). Five punchmarks / One punchmark. Mitch.4166. Toned aVF.
https://www.ebay.de/itm/374268660489?hash=item5724268b09:g:8fsAAOSwFqNjKvm6 INDIA Mauryan Empire Late 4th century-circa 175 BC AR Karshapana 13x17mm, 3,6g Flan with various punchmarks / Taxila symbol punchmark. VF From the Khan Warraich collection