Theygrowupfast:
It's also not too late for your son to do a showcase. As one example, Perfect Game's WWBA 18u tournamnet is an outstanding event for being noticed. As a LHP, your son could probably get linked up with an ongoing team -- everybody always needs more pitching for these things. But if that doesn't pan out, PG will assign your son to a PG pick-up team for the tourney (for a fee, of course).
He'll miss a few days of school, but it sounds like he's strong enough academically to handle it!
In the worst case, you'll spend that last weekend in October playing baseball in sunny Jupiter, FL. Now I ask you, what else would you rather do with that weekend?