Hi Kristin,
If the information on your purchase page and information page is identical then I would question why there is a need to keep them both as physical pages? My advice would be to 301 the new information pages and the old information pages directly to the new purchase pages - this will consolidate all your authority in once place and promote the page which is most beneficial to your company.
However, once this is done I would look to improve the visual aspect of these purchasing pages and see if you can improve the purchasing pages and make them more aesthetically pleasing so that you no longer have a "better landing page" situation like you do at the moment.
The above method require some time and work to be invested - if this is not viable at the moment then I would be inclined to suggest a canonical on the new information pages to the new purchasing pages (rel="canonical" src="new purchasing page").
All the information above is subject to the information being duplicated which I believe to be right. If you have any further questions I'll be happy to help.