Regular CB's - Cobra 29 is a good radio, and so are the higher end
Galaxy radios.
10 Meter - This isn't really legal, but these radios have more power, allowing you to talk farther. I have a
General Lee, and love it. These radios do require a modification to work as a CB, but most of your better CB Shops know how to do it.
This page shows several good antennas. Height and type will depend on the truck, and where they are being mounted.
The links I posted in here are from a CB shop close to where I live, and where I buy all of my CB equipment and have all my work done. I am not reccomending purchasing from them, or not purchasing from them, just wanted to be able to show you some possibilities.
Does he own his own truck, or is it a company truck?
As far as antennas, it depends on where he is mounting them, and how tall they need to be.