Did you find a way? Alas, I don’t think there is an easy way to duplicate the widget. I just had a look at the code and it’s all geared around a single pages widget. The data is stored in a single option.
If you want a second pages widget on a separate sidebar, you could use this plugin I just wrote:
http://www.callum-macdonald.com/download/wp-pages-widgets.php.zip
The reason you need to have them on separate sidebars is that the form variables are the same as the main widget. So if you create two on the same sidebar, the settings will be the same for both widgets.
This is a really simple hacky plugin that meets my needs, it might not work for you. I might eventually code up something more elegant allowing for multiple pages widgets, but not tonight! 🙂