Harris, meanwhile, has three goals and 11 points in 17 games with Northeastern University (NCAA - Hockey East) so far this year.
The 19-year-old sophomore defenseman ranks second on the Huskies in points among blueliners, and also boasts 18 blocked shots.
A native of Haverhill, MA, Harris was selected in the third round, 71st overall by the Canadiens in the 2018 NHL Draft.
Caufield and Harris were two of 28 players named on Monday. The Team USA brass is expected to whittle down the roster to 23 players by December 24.
This year's edition of the World Junior Hockey Championship will be held in the Czech Republic from December 26 - January 5.
The Finns are the defending tournament champions.