The cost for work, including tips and converters bought separately and installed on my 2nd & 3rd visit to exhaust shop was around the $400. U.S. mark.
The major cost was the exhaust pipe work (about $200.U.S.) and that cost will depend on the exhaust shop that you get to do the work. In my case, there was no special deal, in fact this was the first time I had ever dealt with them. They charged me the norm for material and labour.