about 500-600 a piece I have 4 now feeding them a little over 800 a piece and they are fine but thats a alot of power for 10 woofers which mean lots of $$$
Looks like 1.6ohm is going to be your best bet. I'd strap a pair of 2-3kw amps and be pretty happy. It'd be best for you to find out the actual imp of the coils so you'll know where you'll really be sitting.