I have been interested in a set of
crank replacement decals I found on eBay for some Ultegra's. I'm still a little skeptical of their quality because I can see the sticker line in the image but that's also because the camera is 6" away. Standing above a crank is a
much different perspective. With 39 sold, they seem like a potentially good solution.
Clearly these won't work on your exact crank but a quick eBay search may net you something similar.
Of course, in order to slap a new set of decals on, you'd first need to debadge your current cranks either chemically or physically.