I'm afraid you'll have to get lucky to get 1/0 gauge wire at a good price. It's not cheap hardly anywhere unless it is used and someone just needs to part with it. I myself got lucky and got some wire made by a manufacturer that is no longer in business so my local shop sold it to me for $3.50/ft. The other brand of 1/0 gauge they had was almost $7/ft. But the good news is once you do get it you won't have to buy it for as long as you own your system. But hey, I would try ebay just for the hell of it. As far as distribution blocks go they make them with inputs that accept 1/0 thru 4 gauge.....and outputs from 4 thru 8 gauge....unfortunately you will pay good money for a good one of these too. But like wire...it should last quite a long time.