First of all please clarify your question, you say 1000 watts, is this rms or max, there are a ton of amps with 1000 rms that will fix in that hole. As far as your sub enclosure your best shot is going to be ebay to find something used or broken, also, i hope you aren't wanting to run 1000 rms to a bazooka tube because im not sure those enclosures are really meant for that kind of pressure and power(with the right sub).