This isn't a complete list as some manufacturers were left out. There are also other sites out there that provide this kind of data, use Google to search them out. Some of them however aren't up to date because some manufacturers (as I found out) updated their paint stocks as well as their equivalent colors. Made me realize that the scale model paint industry is such a dynamic place and not static like what I presumed it to be.
Kindly read the disclaimer before using this data.