Canon AE-1 underwater housing / MMII-Ex

Hi

I am looking to track down underwater housing system for a Canon AE1
as a relatively inexpensive way to move up from underwater photography
using Aquashot housing for disposable cameras.

I would appreciate if anyone can help me with trying to track one
down. Failing that I am looking for MMII-Ex in full working condition
with conversion lenses, viewfinder, etc for around $600-800.

Thanks a lot,
Kieran