All of these are on sale today at Amazon and Google only, but if you're willing to price match at Kobo (for store credit), the effective price is 10% less than the Amazon/Google price.
Brian Aldiss: Helliconia Trilogy $0.99
Amazon Google Kobo ($15.49 before PM)
Patricia Wrede: The Lyra Novels $1.99
Amazon Google Kobo ($23.99 before PM)
Robin McKinley: Beauty $0.99
Amazon Google Kobo ($6.29 before PM)
Robin McKinley: Rose Daughter $0.99
Amazon Google Kobo ($7.19 before PM)
Some of the Lyra novels were free back in December during the Open Road freebies sale, and Beauty is one of the $15 books in the current Humble Bundle Women in SF sale. Beauty is one of the few that I didn't have from the Humble Bundle sale, so I'm going to get it at Kobo instead.