A3 tdi s-line exhaust tip?

hi guys I'm new to the forum.
I just bought a 2006 a3 tdi s-line 140,and thinking of changing the look of the exhaust. The exhaust at the minute is the twin pipe one that curves down towards the ground. I was lookin at fitting the stainless steel tips to the original tailpipe. Does any anyone no were to buy these from? And can they be welded onto the existing pipes? If so do you do this with the back box still fitted or do you have to take the exhaust off to fit? Any info on we're to buy these from and what dimensions are needed would be great.
Cal

Hi, I would just try your local powerflow or longlife dealer, they should be able to sort some new tips out for you.