Don't forget to look for Dragon's 1/700 USS Charles F. Adams Full Hull kit. It is the same mold as the Cochran and it is more correct for Cochran than for Adams. And there is the Revell 1/700 Rommel DDG kit. It is the same basic mold with additional parts so that it can be German or US or Austrailian. It is based on the Skywave mold so I believe it is waterline only.
ie: D187 Rommel was one of three Lütjens-class guided-missile destroyers, a modified version of the American Charles F. Adams class.
The big question, Would a Charles F. Adams Class Resin kit at 1/350 scale work?
https://freetimehobbies.com/1-350-iron-shipwrights-uss-barney-ddg-6-adams-class-guided-missile-destroyer-1985/
It's much more expensive than the 1/700 plastic kits, but very detailed. And it is available. Try Iron Shipwright too as they may have a discount going on now.
http://ironshipwrights.com/pages/barney.html
If he has not dealt with a resin kit before he might want to get something smaller to practice on. Definetly have him join the Ships forum and we will help him thru any learning curve.
Building a model to start Retirement is the best idea in the world.
Nino
P.S. I have a privare message on the way to you.