The Verdict: Not eligible
The descent claim stops before it reaches you, but your parent may be able to claim. Look also at naturalisation as a person of Greek origin, in our Diaspora and Religious Return quiz.
Until 8 May 1984 nationality passed only from the father. A child born before that date to a Greek mother, in a marriage Greek law recognised, was not Greek at birth. That child can still declare under article 14(1) of the Citizenship Code, but nationality runs from the declaration and reaches only their children who are minors and unmarried on that day.
One exception: if that Greek mother was not married to the child's father, or the marriage was not valid in Greek law (a civil wedding before 18 July 1982 can fail that test), the child followed her and was Greek from birth, and the line may continue to you. Check the marriage certificate first.
So the right applicant is whoever in your line was born before 8 May 1984 to the Greek mother, usually your parent. If they are alive, they can declare in person at a Greek consulate, with no deadline. It will not make you Greek, but it makes them Greek, and any of their children who are still under 18 and unmarried at the same time.
For yourself, article 10 of the Citizenship Code lets people of Greek origin living abroad apply for naturalisation without living in Greece. It is discretionary, but it does not matter that the link runs through a woman.