Does the HG25504 handle pins 1 - 17 and the SED1330 controls 18-31?
I believe that HG25504 may identifiy the LCD module (the printed circuit board with the display, controller, and other components) whereas SED1330 identifies the controller chip (one of the epoxy blobs on the pc board). You would need a decent datasheet for the HG25504 to figure out pins 18 - 31.
Don