Here's the sink I used in our extremely small second bathroom. I wouldn't say the sink is tiny but it's quite small compared to other pedestal sinks. There's plenty of room to use it for what you need, yet it fits in a tight space.

Here is a link that might be useful: Doric Pedestal Sink

Tankless toilets also save a lot of space.

What height is the window? Windows in the shower tend to be higher than in other places...

Now that is very nice. Would go good with the 4.5 foot clawfoot I happen to have.

I see that at the widest point in the center it protrudes about 17.5 inches from the wall. The door has to be able to clear the sink so if the side dimension is less than 16" it will work. (I know its rounded but if you can picture a square side on it would it be less than 16"?).

If you could tell me how wide it is from the left to the right that would be helpful too.

Its kind of tight in there but with the right fixtures it will work OK.

I have almost the same bathroom/same layout and I wanted to do just what you're suggesting - turn the whole window end of the room into a shower. I ran into several problems with this, mainly that I could not find a tub that would work. Most of the short tubs (Kohler greek bath, etc) didn't have an integral tiling flange, so they're not suitable for use in a shower/bath combo application. If you just want to make it into a shower, though, without a tub, that should be doable - someone on this forum recommended a Kerdi shower to me. I've had many apartments with windows in the showers and they were never a problem.

The sink is 22-3/4 inches wide; the sides start at about 14-1/2 inches before it widens to the curve at the front of the sink (17-1/2 inches). My Doric sink is 2-1/2 inches from the wall, and the door clears it beautifully.