I'm not a lighting expert but how about a wall mounted fixture that washes the walls in light. I suppose the wiring runs just on one wall. I'd say a couple would do the job. Fixed spotlights could be an answer but I don't think they are right, perhaps something in smooth white glass.

Do you have electrical wiring in the walls?

Have no idea what the size of that opening is but if you need something fairly reasonable that gives out light trying the Solara? http://www.hinkleylighting.com/products/product-family.aspx?cid=23&famid=395&fid=65
Or do you want something traditional? Its hard to know by just seeing these pics. I also like this one: Spanish Bronze: http://www.hinkleylighting.com/products/product-family.aspx?cid=23&famid=386&fid=158

If you have electrical source in the walls, Anything is possible. A custom made Sconce or even a lighted Wall sculpture suited to your design preferences and the space can be created.

Here are a few examples, Many more unique ideas can come to life here

First we all need to know if there is wiring. We can't suggest anything before thT. You can't open the walls up. I doubt there is wiring.

Well, Even if there is not Wiring, There are options to provide it in a way that will enhance specialized lighting. Having wiring present will simply make it easier.

The more I think about this stairwell, The more I love it. I can see several torch type sconces along the wall connected by rustic chains that can carry the power to the lights.

Dan, you're coming around to my side. Are you picturing a moat and drawbridge, too? :)

Panjatty... Not sure about the Moat and Drawbridge, but these days it wouldn't be a bad Idea...This is such a great space...and your right, I can only imagine what the rest of this house looks like. I would most certainly embrace these beautiful Walls...and with just the right light!

jschembri03 -- any chance of seeing a pic of the outside of your house just to satisfy us 'Nosy Parkers'? :)

Wow! Thanks for the great response! :) unfortunately I do not have any pics of the exterior :/ the electrical wiring for the staircase is on the wall opposite the windows. I have attached some other pics to give you a better idea of the interior....you have to see it to believe it....its a beautiful 400 year old house in the heart of the village core and i'm trying to keep the light fittings as rustic as possible :)

Even more beautiful. I was hoping the rest would match the staircase and I wasn't disappointed! Thanks for the peeks! I would repeat my suggestion to go with ironwork sconces and I would replace the two brass ones shown above, too, while you're at it.

WOW... If Houses can be Artwork, Then your house is a Masterpiece... Anything less than perfect, would not be acceptable... Truly Beautiful!!

So if the wiring for the staircase is on the wall opposite the window, It would be fairly easy to establish power to a light or series of lights along the wall. The challenge would be to create the perfect lighting sconce. If you would like to consider something specially created for this space, I would be more than happy to discuss some options.

Thanks for all the suggestions and help :) I have managed to source a suitable light fitting only with your great help! Cheers!