Well i know that 1 RF power 501bd pusshes the $h!t out of my freind's 1 15L7. So one for each would be awsome, but i dont know if you can get two for 400-475. look on cardomain.com or etronics.com. Do it yourself. it aint that hard if you know alittle. also, wire their (if they are dual 4 ohm) voice coils in parallel to each amp.
check out etronics P6001 600x1@ 2 ohms $379.99 P6002 600x1@ 4 ohms So 1200x1@ 2ohms $389.99 Should be enough dont know too much bout these new amps but last year power models rock. A power 1001bd would be good. try to find that if you like RF.