Is there a performance replacement for the stock 3.5" muffler? 304 stainless steel is preferred.

There is. I will try and get the part number
I had it on my truck befor the 5"
Personally I would just buy 4 or 5 inch

I am thinking about trying a cat delete pipe and replacement muffler. Seems like it may be quite a bit cheaper for about the same qualities.