is it the internal one or external? The outside one should be avail off the shelf at any motorfactors, the internal one is an odd size, the one you need is 12x19x5
http://simplybearings.co.uk/ do em and they aint spensive. However strippign the dizzy down to fit it is a mare of a job, the pin in the end really doesnt like being bashed out. Next time I'm just gonna get another dizzy

Any k-jet 16v will do you, MK2 KR, Corrado KR/9a and Audi 6a. Good luck finding any o these down the scrappy though, but usually theres a couple on ebay. A MK3 Polo CL one will work at a push too, not ideal but it'll keep you motoring. You could also use a non injection vac advance one again just to keep you motoring, if say you had a problem stripping down the 16v dizzy to replace above o'ring. The ignition curve wont be ideal but I've seen plenty of 16v run this way, mostly for show rather than go though

Actually I remember someone mentionign a Pug 306 one fitted but minds gone blank on which one and how they got it working...
Danny is the GT Polo dizzy pretty much spot on for a MK2 16v then?
edit: found the thread, its a peugeot 205 1.9 GTI dizzy which is vac advance and supposedly works pretty well on a 16v. Not done it mesen tho!