JCAdad, this is a difficult question. Many factors come into play as to when to begin showcasing a player. IMO, if you son is a player, and it sounds like he, indeed is, then his sophomore year is not too young to send him to a showcase. The question then is, which one, how much to spend, what are your expectations of the number of scouts or college recruiters that will be in attendance etc.
Perfect Game, the obvious leader in showcase events runs a very organized and well attended event. If you go on their website you'll see that you can request an invite online and I'd say that an event like the Sunshine East would be a terrific first showcase opportunity for your son. He will NOT be the youngest there and because it takes place in June, your son will be in top playing shape. As he gets older, and the premier events are held during the winter months it is much more difficult for the northern player to be at his best. I'm sure you'll get several responses to your posting and other opinions on this subject.
If nothing else, there is so much to be gained by having a young player on the field with some older, and better players. He can see what he has to do to better compete or he can see that he already can hold his own and is on the right track. Good luck.