I just had mine done recently, and I paid $60 for a Silverline stainless steel tip, and $20 for the small piece of pipe plus labor. My out the door cost was only $87 with tax. They used the existing rubber hanger mount, the welding was beautiful, and I couldn't be happier with the outcome.
That's an interesting thread, but those modifications involve more time and effort than I want to put into this. I just wanted to know what the cost would be for a simple side-exit exhaust modification.