Unitec is Otis' spare parts arm. 800-328-7840.

Model number and serial number (should be on a tag somewhere, either on the car top or on the machine/power unit) will be helpful in tracking down what you need.

Here is a link that might be useful: Unitec

Maybe call the Otis people in your area to come and do an inspection? If the emergency crank is in poor shape, maybe an allover checkup is a good idea.