https://thebrokenbindingsub.com/products/the-witness-for-the-dead-and-the-grief-of-stones-omnibus
The Broken Bindings special edition omnibus of the UK English versions of The Witness for the Dead and The Grief of Stones is still up for sale on their website. You don't need a subscription to purchase it and they do ship outside the UK. The printing is limited to 1500 copies, so it's unclear how long it'll be up to order.