I’m highly impressed with the advertised properties of Bambulab’s PET-CF, but naturally it only comes in a black color. I need it to be grey (gray). So, maybe with a couple coats of the right paint, I can have it all? But what kind of paint/primer combination would that be? A 2K of some kind maybe?
This might be a option for you and you don’t have to paint at all 
It would be, except it’s PETG, not PET. The glycol molecule deprives PETG the advantages that PET has.
Ya I did not know if it could be an option or not for your project.
But let us know if you paint the part and how it works out.