You have many options. Mantel kits could dress up the lower half with the upper half addressed by use of furring strips/woodwork aplications, stone veneer, drywalled, etc. here's a link to a mantel kit outfit, there are many more out there.

Here is a link that might be useful: mantel kits

I would go to an antique store or somewhere that you can purchase an antique mantel. A full mantel with sides. It may need to be sanded and repainted or if it is still wood, you might want to just perk it up with stain and sealer, especially if you paint the brick.. I live in
st. Louis and we have many places that have old mantels that have been taken out of houses that were torn down, etc. You can also buy an antique one online. If you dont want a mantel that surrounds it then purchase a pretty half mantel.
also the brick is all one color which begs you to paint or whitewash it. I would also take off the brass doors and get a screen in black/iron or pewter color. It looks like the opening to the hearth might be pretty, curved maybe? I would highlight that. Good luck.

Please don't paint the brick in an antique house.

What is that fake brick stuff? Can't you just knock it off? It's usually a fairly thin veneer. Once it's met its end, you can reassess, and either buy a full antique mantel, with an overmantel that goes to the ceiling, or drywall, and go with a shorter mantel. Bring measurements and photos of your house to the salvage yard to help you pick the right piece. The little bit of detail in your pictures suggests your house is craftsman, so I wouldn't go overboard with a Victorian wedding cake.

I normally would never paint the brick, because I love 99.9% of bricks, but this one doesn't look like it could be salvaged with just a mantel.

I would do an antique painting of the bricks, and paint the mantel white or replace it.

Lisa Laporta on HGTV has tips on how to paint a fireplace to give it an anique look. I don't recall the details but she did that to a house that was For Sale. It looked great. She did this rubbing technique with a couple of colors here and there. It wasn't the typical painting over technique. I'm sure if you go to the HGTV website, do a search, you can find her tips.

Our last house , built in 1918 had a rather ugly fireplace as well. The mantel was brick, formed by the mason staggering and turning the bricks as he reached the appropriate height. It was probably thought to be quite fetching in 1918 and probably continued to be so until someone applied a lot of white paint. They probably thought it was lovely. I thought it was an eyesore, but I had no idea of how to approach it. What I really would have liked was to sand blast the thing to bring it back. NOT POSSIBLE! However my tile guy offered a suggestion which we took.
We knocked off the staggered brick mantel and scuffed up the paint with a mini-grinder , removing about half the paint in the process. We then applied a thinset mixture and faced the fireplace with brown marble, replaced the hearth with the same marble and set in place an old reclaimed mantel with side posts. Fantastic! The trim on the mantel matched the trim in the rest of the house so well that when we put the house up for sale 3 years ago, several viewers mentioned how lovely it was that we had kept the original mantel when we redid the fireplace. So don't give up hope, it is possible to make a silk purse out of a sow's ear.

I'm not seeing what needs to be "salvaged" from the original brick on the bottom. It just needs to be cleaned.

looks to me like you need to scrub the brick, replace the fake brick with drywall and get a wood mantel shelfto replace the stone top if you don't like it.

what should I scrub the brick with?

also why is the chinking between the bottom bricks so thin?