In your version, to do dynamically this will require access to the source code as you'll need to modify our URL rewrite rules class and adjust the web.config file. What you may want to do instead is create a tangible accessories.aspx and accessories.aspx.cs page, and hard code the category xmlpackage you want to call right into the page. Then anywhere on your site that links to c-1-, just change it to point to accessories.aspx.
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