Dora, Delaware City is a little historical town in New Castle County, Delaware on or near the C&D Canal. I have a close friend whose family has lived in Delaware City for 60 years or more. I'd be happy to ask her where historical records for the town are kept or if the family knew of any Sadlers. We work together also. My guess is you could try either the Delaware Historical Society in Wilmington, Delaware or, I know the archives are kept in Dover, Delaware. Yours, Judy Kaufman Landenberg, PA