Ok I finally decided to part with one of my beloved Infinity Beta 10's. I have two of them but I am only selling one. This one is in excellent condition.
It will work in 0.5/0.7 sealed or 0.6-1.0 ported. I believe the recommended tuning frequency is around 45Hz. It's a very efficient sub in a small ported box.
Specs from the manual:
Power Handling = 250Wrms/per coil
cutout diameter=9.37" (It's slightly larger than most normal 10")
Looking for $80 shipped CONUS-obo