This is an authentic Omega Speedmaster automatic blue date watch dial that comes with some watch hands. This dial measures 29.5mm in diameter.
The writing on your dial reads "Omega, Speedmaster, Automatic, Swiss Made".
I have given you photos of your watch dial from every angle. Please use them to add to this description.
If you are not sure whether this will fit your watch or have any other questions, feel free to message me.