I have a will for my ancestor Robert Yeamans that might give you a few Oakley ancestors. The wording is somewhat confusing but I quote as found: "Robert Yeamans, Westchester. Leaves legacies to Susanah Oakley, Drusilla Oakley, Elizabeth daughter of Elisha Oakley and to Joseph Underwood Jr. Leaves to the heir of Robert Yeamans son of Wm. Yeamans, 5s and no more. To my daughter Elizabeth Oakley 20[lbs]. Rest of estate to Elisha, Robert, Elizabeth, Gilbert, Susanah and Drusilla Oakley and to Elizabeth daughter of Elisha Oakley and to Stephen and Nathaniel sons of Elisha Oakley. Makes my brother John Yeamans and son-in-law Elisha Oakley executors." Witnesses - James Perry, Joseph Smith, Hester Yeamans. Dated March 18, 1761. Proved April 3, 1761

Hope this helps you. Are you close to where these people lived and were buried? Wonder if there's a grave in same cemetery for Robert Yeamans?