Ultimately, I did it in Debbie Bliss Cashmerino in a dark grey. The yarn is soft and delicious, the color deep and dark, and though he thought it was going to be too pointy, it’s perfectly round once stretched over his head. (Or is his head pointy!?)
So simple, and finally done. For a while earlier tonight I was convinced I wouldn’t have enough yarn, and was scrambling around the house looking for a similar weight yarn in a more contrasting color. I decided to just go with it, and see what happened. When I brought the yarn through the stitches at the top, I had literally six inches to work with. Phew!
Post-Script: Why is it that while I posted this to the web, he went upstairs and showered and shaved? Please believe me when I say he cleans up far nicer than this shows! :)