Well, that was her former band, so I figured it might be legal. But I also figured it was too easy, so I kept looking.
And far be it from me to tell you how to run your game, but I propose a "no Sex Pistols" rule, or we're going to wear that band out in just a page or two.
Actually, don't take this as a criticism, but we can have a whole thread on musicians wearing JUST THAT RAMONES shirt. Everyone and their daughter has one (well, my daughter has one but I don't).
Also, side bar, but when I grew up - 80's - it was always cheesy and lame to wear your own band shirt. In fact, it was cool to be unpredictable with that (there was a mild uproar of sorts when the nerds in my high school went to see REM at Toad's Place and Peter Buck wore a Maiden shirt on stage; as a sort of resident Maiden fan, I got about four requests for "a couple Maiden songs to check out" in the days after). When did that become acceptable? Maiden does it every show (somehow EVERYTHING they do is cool, though) and Jerry Only of the Misfits does it all the time too. Ace is sort of guilty of that a lot...