How wide is the opening currently? My guess based on the photos is about 5'-0". I would consider expanding the opening to 7'-0" or so and possibly even 8'-0. That would leave plenty of room to maintain the casing on the expanded side and would give you a "wing" wall there at the end of the chest with the lamp on it.

I think Norwood has a great idea. I don't like the idea of a half wall.

From the pics I am fairly confident you will be dealing with a loadbearing wall and as such a beam would be required. Suggest you consider doing just a wider door opening, match height of existing doors and match casing. This will still require additional support (header) but will be less complicated than doing a beam. Either way, this is a structural change and should be evaluated by a structural engineer and a permit will be required for this type of work.

Graham

Joanna Gaines (HGTV's "Fixer Upper") often just widens and heightens the opening. That would avoid the need to install an expensive laminate beam above. Here's an example from season 3 of her show.

I agree that the 1/2 wall would be awkward and you would still have the structural support issues. I like the idea of enlarging the opening the best, but there are flooring issues. The interior window especially with an interesting old window could be very unique.