I do IT work for a living and kinda enjoy working with spreadsheets and data/databases. The thought of doing something like this has crossed my mind before, but I knew it would be a daunting challenge. However, now that you've done a good chunk of the legwork and gotten the item names listed out nicely, would you be opposed to me making some adjustments to the spreadsheet and filling it in as time allows? I have a feeling if we leave it up to whomever wants to that it won't really get done. I'd pick a district and go shop to shop to fill it out which brings me to this...
Admins: I'm also fluent with SQL and working with MariaDB Databases and, since the shopping plugin (I believe) stores its information in a database, could probably write the code to lookup the information through a web interface which would be always up-to-date. Just saying.