I think yours is older than mine, probably going back to the Golden age of Athens/Peloponnesian Wars? I like it a lot.
Yes, you're correct about the dating---It's usually listed as circa 449-413 BC so it does fall into the 431-404 BC Peloponnesian War...and that' a bit of cool historical context .
That's what makes yours a better coin than mine in my honest opinion. Mine may have less wear, but yours was probably held by people who saw the great Socrates and the great Pericles speak or walk down the street, or by people who had the pleasure of sitting down to listen to the great historian Thucydides in person while he recited a chapter from one of his books. And for sure it was held by some of the veterans who fought in the Peloponnesian War. You can't put a price on that! Imagine the famous people and events that the people who held your coin witnessed. If only those people could give us a personal account of what that was like, but at least we have your coin as a silent witness to those who can no longer speak for themselves and tell us about those things.