Have you ever shipped tile form the UK the shipping is crazy and all retailers mark up that is a fact. How do you know 300% markup. Are you comparing British currency with US they do not convery equally . Lots of makers only deal with retailers that is pretty normal. Have you got a pic of the tile you want ? Maybe post that here and someone might have some other company that makes something close .

I almost used Winchester Tiles and wish I had. This was back in 2016, but there were at least two tile stores in the Mpls area that were Winchester distributors. I don't recall any US markup from the British price nor was the tile price out of line with other US made tiles I was considering, but we don't know what you consider reasonable. They are gorgeous tiles.

I bought tile from Original Style’s Odyssey line through a U.S. dealer. Their price seemed consistent with Original Style’s website. Shipping wasn’t negligible, but not horrendous. I love my tile.