Who gives Arya the coin?

Could you please clarify who exactly is the individual or entity that presents Arya with the coin? Is it a person she knows well, a stranger, or perhaps a mysterious figure? Furthermore, are there any clues within the text that hint at the motivation behind this gift, or is it a purely enigmatic occurrence? Understanding the context and the relationship between Arya and the giver would greatly help in piecing together the puzzle of who bestowed this coin upon her.