Green chromate paint was a pretty generic paint. I think the govt. and many mfgs had standards, but I think any paint labeled chromate green is likely to be close enough. There were two somewhat different types of zinc chromate paint, a yellow and a green. The colors of the two were quite different and unlikely to be confused, but within each color the paints were pretty close from mfg to mfg.
As an aside, I bemoan the situation where zinc chromate spray cans were banned as too dangerous, since I never found anything as good for priming aluminum. I know I can apply a conversion coating first and use other types of primers, but that is a lot of work compared to just spraying a primer from a can. Not an issue for use on styrene, but a do other things than just plastic models.