After much ado, we now have a new sink. It's not installed yet, but the counter is re-cut to accept it, and we have it. And nobody played with the price in the mean time, like happened to This D*mn House.
I was figuring the new sink would fit, because it was the same dimensions as the old one (33"x22"). But I figured wrong, by about 1/2" on each side (the countertop guy was very precise with the old sink, I guess.) I cut most of it with my skilsaw and a concrete cutting blade, but I couldn't get into the corners (especially near the backsplash), so I rented an angle grinder and took out the last bits with that. Not surprisingly, it made a huge mess, even with the shop vac going. I got it all cleaned up, the dishwasher pushed into place, and the water supply shut-off valves installed, too. So tomorrow I can hook up the drain, put the sink in the new hole, and we should have a working sink (and dishwasher!) soon.