Illustrator 7.0 had been a massive leap by introducing layers , but it was clunky. Version 8.0 was the refinement.
Use a friend's Creative Cloud subscription to open it and "Save As" a modern .ai file. If you want the nostalgia: Watch a YouTube "speedrun" of Illustrator 8.0. It is safer and just as satisfying. adobe illustrator 8.0 download
This is harder. Modern Macs cannot run Mac OS 9 natively. Illustrator 7