I need to replace the barrel in the door of my Ami, i have a handful from when i bought replacements for one of my old cars. I was just browzing ecas(as you do), when i noticed dyane barrels are different to 2cv ones. Does anyone know if the Ami is different again?

Yes, they are different.
Ami barrels are longer than 2CVs and Dyanes.
My Ami6 parts book shows them as being a DS part number, as of course Ami6 had the same exterior door handles as ID/DS had up to 1971.
I believe that Ami8 may have the same lock barrels as post 1971 DS, but as I don't have an Ami8 parts book, I can not be certain.
Der Francose sell barrel kits for ID & DS for about 25-ish €uros I think.

ahh, didnt think to look in that book! thanks