Here are some resources that might be helpful:
KLOV: Arcade game database (https://www.arcade-museum.com/game-list/0/Videogame)
Arcade Museum Network: Non-profit organization dedicated to arcade game preservation (https://www.arcade-museum.com/)
Shmup subreddit: Online community focused on shoot 'em up games (https://www.reddit.com/r/shmups/)
While identifying the exact game might be challenging, hopefully, these suggestions can help you narrow down the search and find the title you're looking for!