Below are places that sell Bibles and New Testaments in the United Kingdom.
10 of Those
https://www.10ofthose.com/uk/products/bibles
Chapter Two Books
https://www.chaptertwobooks.org.uk/bibles.html
https://www.chaptertwobooks.org.uk
Christian.co.uk
https://christian.co.uk/collections/bible-study
Eden UK
Books, bibles tracts, music, children’s materials
Equipping the Church
http://www.equippingthechurch.com
ICM Books Direct
https://www.icmbooksdirect.co.uk/category/1/Bibles/landing
https://www.icmbooksdirect.co.uk
Living Waters Europe
https://shop.livingwaterseu.com/collections/bibles
https://shop.livingwaterseu.com
The Good Book
https://www.thegoodbook.co.uk/bibles/
Time for Truth
https://shop.timefortruth.co.uk/bibles.html
https://shop.timefortruth.co.uk
Trinitarian Bible Society - England