A quick learner from Manitoba, Canada says:
September 5, 2016
The number on the crank is 14DN982. See attached photo.
Dave from SWISCO responded:
September 8, 2016
Hello. Please look at our 39-253L operator. I believe this is the one you are looking for. Let me know what you think! We carry a variety of other parts that may work for this window, if you need them. Let me know if anything else needs replacing.