Thanks for an insightful answer.
Yeah, these things are old school for sure, easily 20 years old. It says "max 200 watts" on the magnet, so I assumed RMS would be around 100?
Hm, a mono amp with 500 RMS, sounds like something old school should fit the bill nicely. Linear Power, Phoenix Gold or an Orion perhaps (if I can get my hands on one)?