Flush

Hi all
Any advice on where's the best place to get stuff for old Audi cars these days ?
Such as timing belt/tensioner/water pumps etc for 5 cylinder cars - both turbo and non turbo ?
Also whats the chances of getting rubber strips for door bottoms of Audi 90 20v etc ?
Have good intentions of getting a couple of my old Audi cars back on the road for the good weather... ps I am in NI but that doesn't stop me getting stuff sent across from mainland UK.