Here’s a link to the main fencing recruiting thread here on College Confidential. I suggest you read it from the beginning.
Also, note that it’s on the late side for your son to start the process of reaching out to coaches…as many kids in the High School Class of 2018 are already committed to various programs. Hopefully your son has strong results in your zone/internationally? Having some video online where coaches can view selected bouts will help you.
Note that in fencing, regardless of the program, there are only 5 full athletic scholarships available per gender — at maximum. As an “equivalency” sport (vs. “headcount” sport), they can split those 5 full scholarships across more than 5 fencers…and most programs seem to do that (vs. handing out only 5 full rides). That said, depending on your situation, your son may qualify for some need or academic merit aid depending on the schools he’s targeting.
Best of luck. If you can afford the trip (I’m assuming you live in PI), I would encourage he participate in the January NAC here (Virginia Beach), where he could fence in Div1 and Junior (U20) AND possibly arrange to meet some coaches in person. Additionally, I’d advise targeting schools with larger rosters and more international fencers.