If you're trying to prevent duplicate content you should look at the root of the problem. You state that your homepage is using a home.php template, does this include some static text which you're passing to all others pages using the home template? If this is the case either remove it or create a unique home template, which in all honestly should be home.php.
if for whatever reason you want to keep the pages that display the same content as your homepage but using a different URL you can always resort to canonicals.
If you replace the content of your header.php with the following you can specify different headers, one that'll include a canonical that and those that wont.
<?php
if (is_page('1')){
<?php include(TEMPLATEPATH.'/header1.php'); ?>
}
elseif (is_page('2')){
<?php include(TEMPLATEPATH.'/header2.php'); ?>
}
else {
<?php include(TEMPLATEPATH.'/headerdefault.php'); ?>
}
?>
And than you just make sure that you include the canonical which refers to your homepage
<link rel="canonical" href="http://www.yourdomain.com/" />
This will tell Google what is the appropriate URL to the content it's viewing without resorting to using a Plugin.
Either way this all seems a bit weird and I fear that I am just misunderstanding your request as it doesn't seem to make sense. Are you aware of how duplicate content works? Or is it me who should be heading back to bed.
I fail to see the purpose to willingly creating new pages that contain the same content and than looking for a solution to prevent duplicate content.