All good posts here. I know of a crafty lefty here in CA that 2 years ago max'd out 78 at a PG Showcase listed at 5'8" 140 lbs. Our travel team faced him several times over the years & struggled to make solid contact.He is now listed at 5' 11' 175 lbs. & I'm told he sits mid 80's. and is still known as a crafty lefty. He committed to a DI high academic school this past November. I'm sure grades had a lot to do with it, but being a crafty lefty did as well.
My point is that your son needs to focus on the things that he can control, grades, hard work and mental toughness.
Stanford camp, Head first & Showball in CA are great camps. Get him on a solid travel team and make the rounds this summer.
My LHP started his sophomore year. That included making coach contact, in person("Hi I'm a LHP & wanted to introduce myself") & email(Subject Line: 2013 LHP).
My son was never turned away & was always welcomed. Good luck to you and your son!