This is an excellent idea.
Implementation may have some holes. Here's my first search (looking for light bulbs):
https://bangyourbuck.com/search/light%20bulbs/Count/US/grid
I'm getting some good results, but I noticed immediately the item I discovered with a plain amazon search is missing ($1.70/count): https://www.amazon.com/GE-Dimmable-General-Purpose-Replacement/dp/B08T4S58R9/
Also the total number of results is 65 while on amazon I get "over 30,000 results for light bulbs"
Are you pulling only a limited number of matches? Problem is that you can't make such a sort accurately without pulling all results...