The simple solution, which I already had installed, was TabCloud. With the tabs open in my original profile, I saved them to TabCloud, made a new user, installed TabCloud, and restored. From that point, I just closed the window with the pinned tabs last, so that they'd be ready to go next time I need them. You could go from tab to tab clicking stars, too, to save everything as bookmarks, though it's all backed up in TabCloud, anyway.
UPDATE 1/8/12: I have since found it more trouble than it's worth to use a separate profile this way, and I'm just using the saved tab configuration in TabCloud as my work 'profile,' without changing Chrome users. YMMV.