Large murals with datapacks and resourcepacks

Is it possible to create large murals in MC without modding? I've got a project that requires around 200x200 blocks of murals - that's 40000 uniquely textured blocks. I'm guessing item frames and maps are going to kill performance, especially on multiplayer, but I can't think of anything else. MC doesn't have 40k blocks for me to change the texture of. Yesterday I made a java script that takes an image for a 12x20 block mural and creates custom textures for the different states of noteblock, then generates a datapack with setblock commands to autobuild it in-game, but it kept repeating the same few textures so I'm guessing I reached the limit of noteblock instances or smth