What to do with a former window

Hey guys/gals, first time here.

The former owners of our house enclosed the back porch and converted it into an extra room, which we're trying to turn into a guest bedroom. The problem we're having is that the room is adjacent to the kitchen, and right in the middle of the wall between the two spaces is an enormous hole (where the back porch window used to be).

We want to maintain the privacy that a regular guest room would afford, but we also don't want to hire out or break the bank. What would be the most cost-effective and easiest way to cover the hole? We considered glass block (expensive for that size) and shutters (unsure of how to purchase/install). And we want something a little more permanent than curtains.

Any thoughts?