Penguin are releasing the paperback edition of The Sending
on April 24th, so if you didn't manage to get yourself a copy in its large format - and are having trouble tracking down a copy right now - the wait will be over in 10 days.
This paperback format will be 768 pages long (the large-format is 755 pages), and will retail for $22.99 according to Penguin's website
If you can't wait the 10 days to get it, remember that The Sending is also available as an eBook
from both Penguin directly, and via Booki.sh.
The Sending Obernewtyn Chronicles Obernewtyn Penguin