Hello !
I havelots of experience with Excel, i have create standalone ( Visual Basic) and Web based ( PHP) programs, that get data from UPC ( EAN) list , that connect to Amazon VIA AWS Api ( LookUp function) that add some additional info from Amazon MWS api.
For your purpose I would create a script to scrape the required data into Excel file (which can be updated with one click) and then have comparison function in it.
If You need somebody who can manage really difficult thing, I am right person, I am not a guy who use recorded or stolen scripts, i have good background, and all my scripts work with 100% accuracy and performance.
Hope for Your respond,
Regards,
Vlad.