You can use an online upscaler like Waifu2x, although when I tried that for a print, it didn't quite come out that clean. Could have just been the image itself, though, or turning it into a wall scroll as opposed to a print. In the past I've generally just had wall scrolls made since you don't have to worry about frames and they're super easy to put up/take down/store. No doubt that framed prints look better- I don't care since it's shit for my game room.
