Highest rated players we are in on...
WR Amon-Ra St. Brown (5 star): 0.9940 composite ranking.
OT Cade Mays (5 star): 0.099 composite ranking.
OT Nicholas Petit-Frere (4 star): 0.9761 composite ranking.
LB Solomon Tuliaupupu (4 star): 0.9668 composite ranking.
CB Houston Griffith (4 star): 0.9666 composite ranking.
LB Payton Wilson (4 star): 0. 9631 composite ranking.
WR Chase Cota (4 star): 0.9523 composite ranking.
CB Alontae Taylor (4 star): 0.9346 composite ranking.
CB Kyler Gordon (4 star): 0.9157 composite ranking.
WDE Joseph Ossai (4 star): 0.9152 composite ranking.
WR Lawrence Keys (4 star): 0.9139 composite ranking.
Those are the top 250 players (in descending order) that ND has a shot at landing as of right now.
Right now the safest bet at a top player would probably be Nick Petit-Frere (#42 composite player overall). He was down to ND, Florida, Ohio State and Alabama, with the Gators as the presumed leader. Their coaching changes, combined with an excellent official visit to ND for the USC game has most thinking ND has jumped out in front. Ohio State visit is next and we'll know more after that.
As for 5 star players... Amon-Ra St. Brown is ND's best chance at landing one at this point. Cade Mays is visiting ND for the Echoes Awards Banquet and is in the mix, but as if right now, a flip from Tennessee to Clemson seems most likely, with Georgia and Alabama rounding out the top 5. We can't even begin to speculate about ND's chances there until he visits South Bend.
Hope that answers your questions.