Polo outlet is one of the better sources, if you have a good one. Also, some Marshalls -- particularly the larger ones -- offer the blue label suits at about $399. And plenty of folks flip them on eBay, too. Admittedly, it's hard to find a charcoal or a navy this way, but pinstripes and patterns are pretty easy to come by.
The problem with blue label is that a solid in a desirable color can run you as much as a much nicer solid Corneliani.