replace a clip with a different size clip but keep the scale in Premiere CC
After the fact, no I don't.  If you know before the fact in the future though, you can put the source on a timeline by itself and apply the scale there and make all the clips point at that timeline.  This is the same technique I use in After Effects whenever I am working with animating a base layer that I know I am going to need to change.  That way I can make a simple change to the source clip and not have it impact the overall sequence.