Need assistance

Looks like the space you're showing here once took a lock. I'm assuming that this is a casement window. 

We sell a lot of casement window locks, which you can see here, but unfortunately without seeing the original I have no way of making a recommendation. It's very difficult to ID a part without a reference. Would you happen to have another window in the house that uses the same hardware? If so, we can go off of that.

The 38-089 can fit the 38-075 lock. Just make extra sure that your keeper is identical to the 38-089; these kinds of keepers can be very similar in design.