I think its all cars post 93 are meant to have cats, and be checked for emmision ratings, although i could be mistaken. Just had a look on GSF and the only parts i can find are these.
21330 SHORT PIPE 54.5mm G2 1.6 Carb (With Catalyst) 8/88 >10/91 £4.75
21241 EXHAUST DOWN PIPE G2 1.6 Carb 8/83 >10/91 £24.50
Seems a bit cheap really and i always thought the cat was the centre section
