You might start by looking at the local/regional Junior colleges.
Check each to see if they have camps this fall. They are usually put on as a fund raise for the school but they also take notice of HS players. Work ethic and a love for the game can go a very long way with this type of program.
Next try and see if the local big college has a fall baseball league for HS students. A lot of them do. Also a way to raise funds but they also look for kids they can recommend to a JC or maybe even see if the player would fit their program.
The level of play after HS is as varied as what you see in HS. So I have seen and know as well, there is a place somewhere for every kid that wants to continue playing.
The challenge is matching the player to the proper level of play. I am not saying he would be a starter but that there is opportunities out there to contribute and have the college experience with a team. Plus you never know how someone will develop over the next year or two.
And as a coach some would create a roster spot just for a bull nosed kid that gives everything and loves the game. Remember the movie Rudy? They feel that type of player can bring just as much value in how he rubs off on those around him as another utility player that may get no innings and complain all the time. There are JUCO's that I would put against any D-1 program and some D-1's that I don't think could beat our old HS team 2 out of 3.
Anyway I would start there and make sure he plays some where this summer also. His age alone would bring people to a game just to look for players. And you never know a coach may be looking at the other teams starting pitcher but takes notice of your son and his love of the game as well.
GL and let us know how things go.