Copies are listed, both first editions and reprints, both paperback and hard
back, at BookAvenue.com, ABEbooks.com, Bibliofind.com, etc. Prices run $6 to
$30, depending...

The 1916 edition is harder to find and runs $200 and up in decent shape in
the first printing --you are competing with people who collect the
illustrator, N. C. Wyeth. You can probably find a "reading copy" of an early
reprint in ho-hum condition for a lot less, say $30 to $60.

Good luck!

Kevin Mac Donnell
Austin TX