I believe Super Dacob made a video about visiting a pawn shop in Vegas that had a serious luxury bag offering (I'm not making any representations about the authenticity of them, btw, personally). If you can find that video on YouTube, the name may be included. Looked like it was downtown, off the Strip.
Otherwise, you could try Closet Couture down on S. Jones. I have not been there personally, but it has some great reviews on Yelp.