Thanks for the suggestions. I ended up going to Ottomanelli Butcher in Woodside because I've been wanting to check it out. Nice place! Extremely friendly butcher named Frank. Customers are greeted by name, and Frank asked my name, presumably so he can greet me by name next time. Lots of signs hanging about being chosen for the Zagat guide, and a huge one with compliments by Emeril Lagasse. Prosciutto was $19.99 a pound.
Italian Farms also has it for the same price.