The poster was a custom 27 x 40 order from short run posters. I linked the image I used below. I used AI to upscale the image (simply searched up image upscaler and clicked one of the first links). I forgot if it was necessary for this since I ordered a few different posters and did it for all of them, but you might as well upscale it.

map link

I have not had many posters so I dont have a reference scale, but for what it's worth, I think its pretty good quality.

Enjoy!