You would need to rename the whole gang of files to do something like that if you want the actual filename in the URL to read warranty ...

It might be easier to clone a set by do a trace on something like:
page_2
page 2

in the Developers Tool Kit ... to show you were everything exists ...

Then you would need to look into the configuration_keys for this as well ... so that you have control on them ...

In the downloads is an About Us add-on that I believe has both a sidebox and a page of its own that can help you with this ...