I have a JBL/Crown A6000Gti should be repaired in a week, can probably get it to you for about that.
American Bass 500.1
Sundown NS1
Sundown 4500D
Atomic 5K (Cactus 5K)
Crescendo 5K
DC 5K
RD D9
DD M4
Hifonics Sampson (though wouldn't reccomend this to my worst enemy)
There's probably half a dozen more 5KW amps, but they're pretty much the same Korean/Chinese class D circuit as all the other ones with slight variations. You'll find there's only about 3 variations (apart from the heatsink and customer service of whomever's name brand is on it).
Stetsom and Soundigital make some big amps as well. They are actually different designs made in Brazil. Both worthy of consideration.
Any can be had for 700-900$ range used, varying prices used.
More importantly do you have budget and room for a few big arse batteries to properly feed them?