Oh I hear ya on that. Not saying you have to get someone else to do them, but they would know what it takes to get it right.
And they would know where to get correct paint.
Some of those finishes were likely done with special sprayer or at least the tip. I may look into it myself for my grille. Almost a fine 'glittery' finish I believe, when its fresh. But its got a light texture, so not just a regular metallic.