I have M500 and M500t amps and I'm in the same town. I might be willing to lend the amps if you would like to see how they do with the AL-IIIs. Based on my experience with Amazings, they will drive the speakers but you're gonna want more amp. Might be worth evaluating with your sources, though.
It sounds like a great offer and a deal on the Sunfire amp from a respected member. If you are still looking for the right amp, don't forget that you are in the Seattle area which is LOADED with quality vintage and new HiFi, keep an eye on the local Craiglist electronics list. You will find some killer deals if you are patient - buy local, evaluate the gear in person before you hand over your money. [Other than dealing with the fine folks on this site], there is no need to roll the dice online, pay shipping and deal with the usual sub-par packaging /damaged equipment scenarios. good luck with your project.
Phase Linear Andromedas, 2000 II Pre, 5100 II Tuner
Carver Amazings - original and silver, M500t,C-1, C-4000, PM 1.5, M200t
Manley Stingray; Cambridge Audio DacMagic, 640p; Pro-ject Tube Box SE II
McIntosh MC2205, C28
JBL 4430, 4425, 4311B
Rega P5, Benz Micro Wood, Cary/AES AE-3 Preamp