At first, you need a pedal with a thru design, center should be open and accessible from both sides.
Then the pedal should be close to the favero's width.
And finally the pedal body should have the same "logic" to use the same size of stoppers, either from the inside or the outside area. For the outside, let's say you can walk away with some washers. For the inside though... you need a good match.
All these requirements is like "searching for fleas in the hay", that's a Greek metaphor.