I found a pawn shop speaker, a Crate UFM-15H. The horn tweeter wasn’t working but the rest sounded good, and $26 for a new coil later it’s all happy. I’m modding the crossover board to add fuses to prevent that kind of shit but I need another drill bit to surface mount the cartridges. (Fuses you can only change by opening the case are fuses that end your gig.) Tomorrow I will buy this.