I went with a stainless steel down pipe and aluminized steel after the muffler, for no particular reason. The specific parts are used were:
Downpipe and
After Muffler. All parts came out to ~$300 (including muffler), but that's doing everything and fabbing it up myself (other than cutting a couple sections on the elbows between and flared end and the bend and re-welding to modify length, the flange was really all that needed fabbing.. Cut the original flange off the stock exhaust and modified the downpipe for it to work, and it came out perfect).