Seleukos I commemorated his politically and militarily important encounter with Chandragupta in coins with pictures of elephants; this one also depicts Alexander's horse Bucephalus

Source: http://www.vcoins.com/ancient/civitas/store/viewItem.asp?idProduct=8223&large=1
(downloaded May 2006)

"Seleukid Kings of Syria Seleukos I, Nikator 312-280 BC 22. Æ 22 7.78g. 22mm. Apamea mint. Elephant standing right. Horse's head (Alexander's Bucephalus) left; anchor below. [B]ASILEW[S]/SELEUKOU. Struck at Apamea, where the Seleukid stables were kept. The elephant commemorates the tribute of 500 elephants paid out to Seleukos by his Indian adversary Chandragupta, in exchange for vast territories in 303 BC. These were later used against Antigonos."

Some of his coins mythologized the elephants into horned creatures drawing Athena's chariot

Source: http://www.vcoins.com/ancient/bpmurphy/store/viewItem.asp?idProduct=3939&large=1
(downloaded May 2006)

"Seleukos I. 312-280 BC. AR Tetradrachm. Seleukeia on the Tigris mint. 26mm (17.19 gm). Struck circa 296/5-280 BC. Laureate head of Zeus right / Athena Promachos, brandishing spear and holding large shield, in quadriga right drawn by elephants; anchor above, N, monogram and K in exergue."

Others of his coins emphasized only his Greek-ness

Source: http://www.vcoins.com/ancient/ane/store/viewItem.asp?idProduct=831&large=1
(downloaded May 2006)

"Seleukos I Nikator, 312-281 B.C. AR Tetradrachm (26mm, 17.18 g) EF Seleukeia in Pieria Mint. Obv: Head of Herakles right, wearing lion skin headdress. Rev: BASILEWS  SELEUKOU, Zeus Nikephoros seated left; monogram in left field, KP below throne."

His successors in the Seleukid dynasty continued to depict elephants on some of their coins

Source: http://www.vcoins.com/ancient/ancientimports/store/viewItem.asp?idProduct=7802&large=1
(downloaded May 2006)

"Seleukid Kingdom Antiochus III AR Drachm / Elephant. Date: 223-187 BC. Obverse: Bust right. Reverse: Elephant walking right, legends. Size: 18.11 mm.Weight: 3.9 grams."

What may be Chandragupta Maurya's own coins were punch-marked

Source: http://www.vcoins.com/ancient/ancientcoinscanada/store/viewItem.asp?idProduct=1822&large=1
(downloaded May 2006)

"Nice silver karshapanas of Chandragupta (ca.320-300 BC) [if they can be so ascribed], Mauryan Empire. Irregular flat silver plachets. Many punch-mark symbols."