Due to the original fanatec oled is 2.7" and there is hard to find replacement part.
So I use 2.8" 25664 oled to replace 2.7 " one.
But the side of 2.8" can't fit the original frame inside DD2 base, so I use this frame and put it outside DD2 base.

You could buy any 2.8" 25664 graph oled as the link.
https://www.aliexpress.com/item/1005005062566698.html
The things must notice is SSD1322 and 30pins.
So if you interest big side oled, you could use 3.1" or 5.5" one.

You may need watch this video first to know how to teardown dd2.
https://www.youtube.com/watch?v=MDiQ9zmqOss