JohhnyBaseball, one thing you might want to do is spend a couple hours on the PG site, looking at the recruited outfielders at your son's target schools. There will be wide variation within D1. When you look at the data, you will see some schools who recruit outfielders who run 6.8 or 6.9 or even 7.0 as juniors in high school (which doesn't mean that they aren't 6.7 or 6.6 in college, but at this point you are focused on getting recruited).
I have done this kind of legwork for pitching, but not for outfield, but I would suggest it would be worth your time. Just by way of example, here are two of the three outfielders in the (current national champion) University of Florida 2019 recruiting class (the third doesn't have a 60 time listed):
www.perfectgame.org/Players/Pl...ofile.aspx?ID=379789
www.perfectgame.org/Players/Pl...ofile.aspx?ID=438778
As others have mentioned, if your son is at 7.03, with a little speed work he may be able to get to a 6.8 or 6.9.
Good luck to you and your son!!