The 2023 NPB draft was held today and for the first time since 2018, I don't have any "pre-rookie" cards of any of the players.  For the past four years there were at least three players each year who were in either the 2019 or 2020 Panini USA Baseball Stars & Stripes set as representatives of the 2018 or 2019 Collegiate Samurai Japan team respectively.  The last two players to graduate from college were both drafted last year (Shota Morishita and Ryosuke Kodama Mikiya Tanaka) so I was left to wonder if any of the ten players from the teams who went to the corporate leagues after college would be drafted (assuming any of them are still playing).  None of them were so there's a very good likelihood that all the players from those sets who are going to get drafted have been drafted.  The youngest player from the group is Kento Ogo who turned 25 about a month ago so they're all getting a bit old to be entering professional baseball.

There is, however, another possible source of "pre-rookie" cards for the drafted players.  In 2021 and 2022, JABA (the Japanese Amateur (or possibly Adult) Baseball Association), the organization in charge of the corporate/industrial league, issued baseball card sets.  The 2021 set was supposedly 90 cards but may have actually been a little larger - I've been attempting to put a checklist together and I've seen card numbers as high as 92.  The 2022 set is reportedly 88 cards.  Each set contains players from various teams in the corporate leagues.  I've identified roughly 80% of the 2021 set so I compared the list of players drafted from corporate league teams today with the checklist I have and found exactly one player who already had a card - Shunya Morita of Honda Suzuka, the second round pick of the Yomiuri Giants.  He is card #33 in the set.  I don't have this card but I swiped images of the front and back of it from an auction on Mercari (the auction is for three copies of the card which explains the "x3" on the image of the front of the card:

Morita brings the number of known players from the 2021 set who have been drafted to six.  There may be others - I'd actually be surprised if they're aren't - but until I see or generate a complete checklist, I won't know for sure.