They are just like the Mach 1 tips but they fill the cutout better. Summit Racing has them for about $25 each and it cost me $35 to get them welded on at a no name muffler shop. If I were to do this again, I would get the 18" long ones. These here are the 12" long ones.
These are some magnaflow tips 4" I had on my 03 Gt I use to have. I got them from performancepeddlar.com they were 35 or 40 dollars a piece and they are stainless steel. they are 18" long.