Hi there,
A relatively old post on this from the Moz blog might be of use: http://moz.com/blog/how-to-solve-keyword-cannibalization
Have you done any link building to the primary vinyl banners page? When a range of different pages rank for one query, it can often indicate a problem with the strength of the primary page, with site hierarchy not favouring that page as the canonical source of generic information about the topic.