This was a custom window built to suit this particular configuration. It is a company in Los Angeles and I can give you their name if you are in my area (give me some time though, I'm on vacation). I would google Custom Windows and see what companies are in your area. This window hung from a tract and there was no tract below. This is fine if there is a large overhang and you don't have to worry about the elements.
Hope this helps!

Thank you for the information. I'd love to have the name of the manufacturer when you get back from vacation. Thanks so much!