Benefit was called Best Value Guarantee, discontinued ~2006.
yup, i remember that from 10+ years ago!
up until recently, amazon would refund me for price differences within 30 days. then it became 15 days or so, then only TVs, and now i think they no longer do it but may be worth a shot asking, especially if you are a decent volume buyer.
amazon used to also be very flexible in taking returns. now their system wont let you process the return if its over 30 days but you can still do it by contacting them.