looking for replacement crank

Hello Greg. This looks like our 39-031 and 39-032 EntryGard Operators. Just make sure all the dimensions, including the link arm lengths, match your old hardware. Let me know if anything differs. For a new handle and cover that works with this operator, see the 39-114L and 39-107. Your window's hinges look rusted also, so you may want to replace them. See the stainless steel 36-004-10.