I think I answered this once before?................Hi, With the Internet and international shipping, getting samples of a tile you see on Houzz sent to you is a viable option. Then having it matched would be easier. Though. Come to think of it, is international shipping and ordering on line cheaper than custom manufacture? Look into both!

Most my doors were already here, but I did have one moved over, about 6 inches. However, the entire space was demo'd, and rebuilt, so that's not the best example to draw from. If you want the door hidden, in a pocket, yes, you will need a skilled carpenter. Essentially, the opening header and frame, will become twice it's size, with the "pocket" part, hidden behind the wall. The studs/supports will need to be removed to make a space for the door to slide into. Do you have any switches or outlets on the fireplace wall?

How do you decorate your place, what kind of style, colors, and feelings? That will greatly influence the type of door you might want. Also, think of your budget, and whether you want to install it yourself or hire a professional (you don't need to tell us, just keep that in mind). Then look around Houzz, in the products page, they have lots of interior sliding doors and hinged ones, from elegant frosted glass in a dark wood frame, to rustic reclaimed wood planks. You may not want to purchase that exact model, but it might give you a better idea of what would fulfill your airflow needs without sacrificing style.

First of all the images you posted you cant make anything out what you got there. Secondly you should contact a local Architect when doing something like this, not only for structural reasons, but window design as well. He will layout window detail based on the window sizes available from a certain manufacturer or you can take his drawings which indicate opening detail to a place who sells windows, and they have catalogs of window combinations and sizes to make it work with what you have.