This is a ten-speed Campagnolo Veloce shifter. I noticed it sits too far back in the lever body, and now I see it's broken and is about to fall apart. These things are supposed to be rebuildable, so how do I buy a replacement? One idea is to drop the bike off at my local bike shop, but are these things obtainable online? I assume I can either find a service document or figure out the procedure somehow.