Glad youb are sorted, mine was also broken when I opened it in Jan - but it was more like it was stripped, the white cog just turned in the top of the paddle fitting without actually opening or closing us. Made no noises, rattles at all however, I just removed the paddle and re-installed it until the new one arrived.
The local dealer pricing was mad, so I bought from a German dealership through a mate, was 165 Euro. The steel pin can not fall in while the Disa is installed, I'd guess the horror stories are all from them falling out during removal or installing of the Disa - not while in use !
Crazy that we can't get these from Diesel Electric - they are made by Bosch.