Couple more tests:
The two on the right you've seen already. The one on the far left is Rust-o-leum grey primer with the same black and white speckling the second in from the left is the same combo but with some silver added.
![]()
From the picture, and I'm sure in person it may look different, but the far right one to my eyes is the best match so far in terms of color, size of speckles, etc. But that's just me.