I don't know if you can get it your way, but over here there's a mousse that's got a mild bleach in it, and it works as a leave-in conditioner. It takes about two or so weeks to really get results, but it's a gradual process and you can get a mousse that's suited to your hair (ie, you can get a lightener if you have black hair that will take you to a mid-brown, there's a brown mousse to take you to a dark blonde, and for REALLY DRAMATIC BLEACH there's a superblonde that I never had the heart to try) -- it worked for me when I was growing out my bright red Agent Scully hair and took me to a nice sorta honey colour. I *think it's by Sunsilk? It's great because you can control how much or how little you want to use.

I have no idea if it'd be of use, but it might be worth looking into?