Thanks for trying, guys, and let me know if you see them passing by... They are for my wife, who wanted them anyway, but of course it's cool to know if they were ever shown onscreen and where. They say that they were worn onscreen, but the episode is "not specified". This could mean that they were worn, but not really visible, I suppose. Or that they haven't been able to track the episode, which is what I'm hoping for.
The only things that fit me are Boyd's clothes, and I got some of those for myself; they are clearly visible in "True believer" (red sweater etc) and "Hollow men" (jacket etc).