Never go to a PG showcase until you already have D1 measurables. There is no "getting on radar"; there is only having the numbers that coaches are looking for. If you to go PG and put up inferior numbers (no matter what your age), those numbers will stay on your profile and you will then feel obligated to pay for another showcase later. Why waste the money now? You may discover that there was never any need to do it at all.
HA schools recruit starting in the fall of junior year. They need to see grades and test scores. If you have the numbers then (height and velo, grades and test scores), you can send them directly to those schools.
Edited to add: or, better yet, by summer before junior year, you will have reputable HS or travel coaches who will contact colleges for you.