I'm really sorry about the long wait, I don't know how I missed this before!
I just looked into this and it seems there was a mismatch in how TCGPlayer.com (our US card price source) names the Kaladesh Inventions set and how it was recorded in our database. I have now fixed this and updated the prices, so Sword of Feast and Famine
should now finally show up with the correct price!
Please let me know if there are any other issues like this!