I have 4 APX 818 motors I might be willing to part with for the right price. I can build them to 10-21" in dual 2,1.4,1,.7 impedence and however many spiders you request. Or, you can just get the motors. Make an offer.
I have a guy out here that just bought an 18" APX and he's planning to buy one more soon. I just got in a new Atomic 5000.1 amp, just waiting to get subs to burp it with. Atomics make pretty sick amps & subs, one reason I chose them to be a sponsor of some of our SPL shows here in New England this season.