Walker Zanger and Ann Sacks are 2 of the most expensive tiles there is. . Both are ceramic and not a marble so you know. ( I mm pretty sure not marble) The 4″x8″ tile size alone is difficult to find. . In fact I don t recall any 4×8 unless you go to a commercial tile. 3×6 is the most common sub way tile. .
But a couple less expensive makers ( much less!) are American Olean, Dal Tile Florida Tile, and Inter Ceramic to name some I know have 3×6 sub way tile. .
Any questions you can e mail me through my avatar. . GL
Edit. . Curiousity got to me. . Ann Sacks does make a marble tile , but the only size I saw was a 3×6 sub way tile GL

I have searched all over the internet after deciding that local tile stores do not carry high end Carrera and the premium stores that do want your first born to be able to get it. However I have searched online and found various websites, there are in fact two, one is in Ontario, CA so big concerns about buying from Non-USA and non English speaking company, the other is in New Jersey but just sells mosaics, so you cannot complete a room – or put together the whole room, with Subway tiles, 12×12 Carrera floor tiles and a mosaic with matching Carrera CHair rail and Carrara pencil – except for http://www.BuildersDepotDirect.com they offer the Subway tile for $7. 00SF and all the other Carrera matching tiles for the same price, I bought their matching 1″ Hexagon for $10. 95SF and the pencil bullnose 12″ was only $11. 49. I priced it out I saved $5,658. 78 buy not going through Walker Zanger – Ann Sacks even more. Also there is no tax, no tax to pay online – a 9% saving right t It is amazing – long live ecommerce and good people that just work hard to get you excellent products and an awesome price!

Oh the 4×8″ Carrara is $7. 50SF from BuildersDepotDirect.com

I just bought some Daltile brand tiles. The link below will take you to the manufacturer’s website. They only sell wholesale so you will have to go through your dealer. I know that many of their tiles come in a variety of sizes and trims.