That is some beautiful material. The value beyond $8 - $10/bf for generic walnut around here would be specific to the material and your value of it. I know that does nothing to help you. Much like the furniture we make out of things, the value of those things can often be set by the observer / purchaser. Before I started doing this just for myself I would sell a large, figured, book-matched chest of drawers for about $4k. About 1/2 to 2/3rds of that would be materials (wood, glue, finish, environmentals, hardware). If you have a desire (or a buyer) that will cover $100/bf then yes, it is worth it. I can find some pretty beautiful material nearby if I spend my time instead of my money. I'm afraid that in the end placing a quantifiable number on an aesthetic is pretty subjective.