How compatible are toilet repair parts?
Anecdotal:

I had to replace the lever in my Toto toilet. I went to the store, asked for a lever with a dual 45 degree bend "S" in the lever. The guy got me one. I had to return it, because Toto has multiple lever models with dual 45 degree S bends in them. I never thought they were that specialized.

In short, it depends.