Clara carries the Red Old School Satchel by Deena & Ozzy of Urban Outfitters. There are many alts out there, but the SA purse is very rare. The best alt available a style alt also by D&O. It is identical in in construction, the coloring, and the texture of the leather. The only difference is that the straps don't go all the way over like the SA straps do.
Worn in: The Snowmen (outfit #3), The Snowmen (alternate outfit #3), The Rings of Akhaten,Hide
Urban Outfitters Deena & Ozzy Satchel in Tan
Worn in: Into the Dalek (outfit #1)
Urban Outfitters Deena & Ozzy Vintage Style Satchel in Black
Worn in: Into the Dalek (outfit #2)
Coast Peony Clutch in Blue
Got a late ID, so these will probably only be found on eBay and other resale sites for a while.