for my 1999.5 b5 a4 my stock one is rusting and looks quite ugly

i see the oem direct one from ECSTUNING, is it as easy as jacking my car up and unscrewing the bolts?

is it possible to get a single tip from the dual one the stock/oem tip is? thanks

 

I'm not seeing tips sold separately from the muffler for your car, for 4 or 6 cylinder cars. So to answer your question using OEM parts I'd have to say no. To get just the tip, you'd have to go aftermarket or to ECS where you found that one you mentioned.