For the episode, this was the original belt which was then heavily modified. The buckle, which was originally shiny aluminum, was scuffed and the three rivets were ground down flat. Then a patina or other aging chemical was rubbed in and wiped off, staining the crevices. The metal pyramids were removed. The belt loop bar which holds the leather in place was removed, and moved down to the leather. The leather, instead of being allowed to hang down, was folded behind itself and slid back into the bar. That's just how the belt itself was altered, we haven't even started on all the crap that they added to it. They sold this belt on the website specially for cosplayers for a long time, so a great many people ended up getting one.
Worn in: Asylum of the Daleks
Gucci Reversible Red Blue Leather Belt
This belt is not commonly sought after, but c'mon. Red and Blue reversible; it doesn't get much more Clara than that. Jenna wore this belt in her first promotional photos as Clara.