It is a souvenir token from the Greek Tourism Organisation. The text on the back comes from the Odyssey (14.58), and this token shows Xenios Zeus, or Zeus [protector] of the Foreigners.
The text translates as: All vagabonds and strangers are under Zeus, and the gift is a light and a dear one.
I googled the inscription, and this came out as a result.
https://www.coincommunity.com/forum/topic.asp?TOPIC_ID=30630
The images, for some reason, don't match the items described, however the description does.
Try asking the organisation to see what they have to say
https://twitter.com/visitgreecegr