Any question answered...

Cheers Tom, appreciated. I have found a few places that list them but they are all out of stock and unable to say when they will have new stock.

They are fairly complex things but I'd be willing to have a go at trying to fix it or to pass it to somebody to have a go.

I leaned into a corned and stacked it about 6 months ago and it has not ratcheted since. My creaking legs are demanding that I am able to shift to my little ring nowdays.

I know that this one is tiagra but it might be of some help on how to repair them;

http://www.cyclingcrowd.com/Uwe/Forum.aspx/technical/11398/tiagra-9-speed-STI-shifter-maintenance

It's probably worth giving it a go you'll either fix it or it will be broken just like before.