I don't have Facebook so I can't see those
You dont need one because that profile is public, it will likely ask you to sign up, just click no.
As for your castings, they are going to blast them at the powdercoater. I pay about $250 for the parts and I tend to use
https://www.prismaticpowders.com/ they also have an applicator finder on there to find someone good!
TFT