Heres what I have been rolling on bottom of our 69. I just noticed 1 is semigloss and 1 flat black lol. Got mine at Canadian Tire. Employee told me it was Rustoleum company?
For the semi gloss black you can actually get the semi gloss black at Canadian tire iirc. That's where I got mine that I coated the bottom of my car with and the k frame.
You can get Semi gloss in a spray can, but I've yet to see it in a paint can and I'm not going in a store again for a long time if I can help it. Thanks!