Not sure about REST but you can do it with Bob Swift Confluence CLI plugin
After you install it on your client machine you can run command line command as the following example:
confluence --action addBlog --space "zconfluencecli" --title "addBlog1" --content "This is a test page." --content2 "link: [google|http://google.com]" --dayOfMonth 1 --month 2 --year 2014
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