Ideally you buy the sidelights and transom windows as a whole unit with the door. It's a lot more energy efficient and a heck of a lot easier to install. Since it looks like it was previously an existing unit that would be the way to go without doing a lot of major rework. You would hire a carpenter to do that or the installer from the window/door place you buy it from.
OK I didn't see the brick on the bottom. But you still should be able to find a fixed window that size fairly easily. It's not going to be at a big box store though. You have to go to a real window and door showroom. Standard sidelight widths are 10, 12, and 14". It might have to be put together in pieces vs. one big unit but it will look a lot better than some piece meal job with a door that doesn't match the transom or sidelites. How are you going to trim out the door from the outside and how will that match the transom and sidelite trim? Are you replacing all of the exterior portion or trying to keep part of it?
You look like you live in an area that gets cold weather. Wouldn't a double pane insulated transom and sidelites be a lot better? Besides the doors from HD are not the best (at least in my location they aren't I know they vary from store to store). Is it a steel door or fiberglass? What is the jam made of? Does it have ball bearing hinges? Is the glass double pane? What is the R-value of the door? What does the cross section of the door construction look like?
When we redo the exterior in a couple years we're going to use a similar looking door from Therma Tru:
There are companies that just specialize in installing doors and windows. They might be a place to start especially with your sidelights and transom. They could let you know about whether the original structure can be salvaged and the glass replaced (and cut and install the glass and door) or if you should actually buy a whole unit. Otherwise, I would look for local contractors who specializes in renovation and try to get a few of them to come out and give you quotes.
I'm going to also not answer the original question- I can't see the rest of the building, but it's not a craftsman is it? I think you should get a door that matches the house or it won't be much of an improvement.