Broken Part

Sure, I feel confident we can help. Now, I don't think we have an exact match for this, but we have a couple different lock sets in this style so odds are good that we can get one to work. 

I note in your third picture that you have a little turn lever at the bottom end of the housing, near the screw hole. With that in mind, I recommend the 82-002. This has a flip lever in the same position, which means the hook should come out at the same place. Look it over and let me know what you think.

We also have a keyed version, if that's something that might interest you. See our 82-002K.