When my older 88 key controller started blowing out the velocity rubber pieces, and the velocity on those keys were much louder than others, I also went on a search because repair parts were hard to find. I cured it with a little VST called Veloscaler by CodeFN42. It works very well and is FREE!
Corky
BTW, here is the thread where I was asking the same question.
Also, if you read above my comment on Veloscaler, @Torsten gave a great example of the possibilities within C3.