immi09 - Your contact have been saved. Nice Beetle buddy, seems like you've kept it with enthusiasm Try getting some genuine parts according to your model, e.g rear lamps, side mirrors, steering wheel etc if you find. I'll also let you know if I come across some. Also post some of its engine pictures.
About the silencer, it depends on the condition of your current one. First get it checked by your mechanic, or you can go to Main Market Gulberg, one of the guys there works for VW silencers. You can ask any of the mechanic there he should be able to guide you to him.