My original post was https://realstmfc.groups.io/g/main/message/161417 but the photos do not appear to be attached so I will add new ones here. My recent blog is linked in my signature. There are new colors added and you can see it is nice to have a sample of discontinued products on a card nearby to compare to and decide what matches. As a good researcher my aim is to provide information in the best way possible, explicitly point out the limitations of the information (photographed with 5000k bulbs), and let you decide. I will offer conclusions but ultimately you decide what works.
For example, to me Vallejo Red Leather is similar and maybe a little light to match PollyScale Zinc Chromate Primer, which I have used on several post war B&O boxcars. I will do some experimenting to see what I think might work.