You might also contact B&W tile which claims to reproduce tile from the '20s to the '50s. Bad website, so you can't see the colors. If you look closely, you'll see they also make patterned deco liners like the ones in your bath.
Mission Tile West also has a revival classics line, and their colors seem to vary. They give no info online regarding allowable grout lines, though, so you'd have to email or call.
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7' wide island, 10" wide pendants
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