Suggestions for New Exhaust

[Facington]

i ahve a 2004 cbr600f4i; an idiot friend knocked it over the other day; framesliders saved it; but muffler is all scratched up (stainless steel stock);any suggestions on the cheapest way to replace it; and would it be worth getting a new yoshimora or other slip on; and how do i look for ones that will fit my bike, or are they all standard? Thanks