This is probably the closest match to parkerizing that I know of short of buying the chemicals to do parkerizing. It's what I put on my Delisle build that I did last year.
You do have to have an airbrush and bake it in the oven at ~300 for an hour after it sits overnight after painting it (at least overnight) to keep the fumes down.
It's not bomb proof (though nothing is). But it does hold up a lot better than paint. There's a lot of tech info on their website about salt water and acid corrosion testing and stuff that was done before they could sell it to the DOD/navy seals, but it's what I use for myself.
This is a grey black (old school Colt grey anodizing). They have other shades as well. If you want a matte finish, heat the part up to about 100 or 105*F just prior to spraying.
FWIW, this is a matte finish that I wanted on this old gun because of historical preference. If you've never heard of a Delisle, that's OK a lot of people haven't. And even a lot of unfortunate Germans never "heard it" either.
https://molyresin.com/shop/8oz/
Here's their socom black on another silencer build that I did.
I had to remove the anodizing in order to do the electro-etch engraving and then refinished it in socom black.
I did colorfill the .45 text with white, but you can't really tell the difference in the black.
Come to think of it, I did the lower receiver in it as well. Here it is raw/in the white
After sitting all night airing out and flash curing, before baking: