In an effort to restore them as much as I could, I used a combination of waifu2x ("Single-Image Super-Resolution for Anime-Style Art using Deep Convolutional Neural Networks"), Clip Studio Paint resize/cleanup tools, and manual cleanup done by hand. Unfortunately, the red text on the title page was a lost cause. If anyone can decipher solid red rectangles please contact me lol. Source: about 1 year ago

Maybe this would help. There's also an app version of it. Source: about 1 year ago

I would recommend putting it through an upscaler beforehand, it seems a bit small. Source: over 1 year ago

Http://waifu2x.udp.jp/index.html found this image upscaler from https://www.reddit.com/r/FireEmblemHeroes/comments/a51f0k/i_turned_yusuke_kozakis_artwork_into_a_high/?st=JPIZKYIB&sh=f12f76fe a while ago, perhaps that would be the closest if IS doesn't release anything. Source: over 1 year ago

You can make it bigger for print by using by using an Japanese AI image enlarging tool. Source: over 1 year ago

Have a look on https://sketchmob.com/ , has many different artist with a variety of styles and price ranges. I use this site a lot. Source: over 1 year ago

If there's a particular artist whose style you like, see if they do commissions. Maybe try searching for the characters on DeviantArt to find an artist who already has a familiarity with the franchise. You can also get art done from sites like Sketchmob (though, you may need to find some reference photos to give the artist an idea of what you're thinking, I'm not entirely familiar with the procedure there). Source: over 2 years ago

What's more important is this beautiful work of art! We have an excellent piece by "mapo_tofus" on sketchmob.com of Lucina playing the clarinet. I essentially held an amino poll with 5 characters to potentially be drawn playing the instrument, and Lucina won, and I actually wanted Lucina to win anyway, although you might be disappointed when you find out who she won against. Source: almost 3 years ago