Tile something using real-world dimensions?

Support Materials and Textures
10

Try this:
TestTiles.blend (1.5 MB)
The result with included texture:

TestTiles
TestTiles3840×2160 1.85 MB

There is an output socket ready if you really want only random 90° rotation.
I didn’t include hdr. I also suggest replacing texture with a high res modern one.