I have a stock exhaust system from a 2009 Challenger SRT-8 for sale. Outside diameter of the exhaust is 2.75". Manual transmission car. There are about 200 miles on the exhaust when it was taken off. No rust. This might be a cheap way to upgrade the exhaust system on an R/T Challenger, not sure about that though you will have to research that.

Pickup only I am in Pottstown, PA 19465. I'll drive up to an hour away to meet someone. Lookin to get $200 for it or make an offer. PM me.