A few minutes ago, we implemented a bugfix for the incorrect prices.
Vindicator’s gear has universally had its cost reduced in Honor Points, and Marks of Honor are no longer required for any piece, as intended.
In Season 4 next week, Guardian’s Honor pieces will have their Marks of Honor cost universally reduced by 50%, but their Honor cost remains as before, as intended.
Thank you for your reports and helping us track down this bug.