Order at list price via any online book seller.

https://www.booksamillion.com/p/Two-Years-Another-Planet/David-Bernknopf/9798318814518

https://www.walmart.com/ip/Two-Years-on-Another-Planet-or-is-it-Alaska-Paperback-9798318814518/19659367500?classType=REGULAR&from=/search

or Amazon and Barnes and Noble