The blog example from the tutorial deals with this kind of stuff: http://docs.jboss.com/seam/latest/reference/en/html/tutorial.html#blog
This example calls an @Unwrap-annotated @Stateless session bean directly from the JSF page being loaded. As far as I can tell the statelessness ensures that the data gets loaded fresh every time.
And check the section of the docs that describe Seam page actions.
I've been using page action in the pages.xml file, usually together with @RequestParameter