It can't be Greek. The classical Greek alphabet doesn't have letters shaped like S, C or G.
It's actually a token. Specifically, an Irish "Conder token", from
Enniscorthy, county Wexford. There are apparently a dozen varieties known of this token, listed in the Dalton and Hamer book of Conder tokens as Wexford numbers 5 through to 16.
And no, I didn't know this beforehand; I'm no Conder expert. I don't even have a proper D&H book. I found
This site with an example of one of these tokens,second from bottom, by typing '"payable at" bank phoenix token' into Google.
In case the Doty reference link dies at some stage in the future, here's what your token should read like:
Obverse: Phoenix over RW cipher, FOR CHANGE above, the date 1800 below.
Reverse: text only: PAYABLE / AT / WOODCOCK'S / BANK / ENNISCORTHY.
A pity yours is so badly beat up; Dr. Doty's example is described as "RARE" and sold for $95.
I still learn something new every day from questions asked on this forum.

Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis