I have a couple of damascus gyuto blanks I am finishing, and I'd like the bolsters to be mokume-gane.
I've found jewelry grade billets, but nothing suitable for a knife.
Maybe here? http://www.sakmarenterprises.com/
I'd highley recommend contacting Phillip Jones of Jones Bros. Knives. http://www.customknives.com/jonesbrothers/ Phillip is a good friend, and his mokume is excellent. My fiancee has a pair of earrings made from his mokume that are quite beautiful.
I bought here http://www.chadnicholsdamascus.com/mokume
You won't find it made better than Chad does it. I've made plenty of his mokume and ss damascus into jewelery and it's always flawless stuff.