Guys- thanks for the referral! I've sent Daniel a PM with some prices, etc. 16/4 and 8/4 oak is not very common (nor inexpensive), so one option for him may be laminating some 4/4 stock together or gluing up a post with four mitered corners.
Last time I built a bed, it called for 3 x 8's for the bookcase headboard. I laminated (face glued) 3 x 5/4 boards and it worked out great. It's one of the very few times I used gorilla glue.