Where to buy silk comforters in Beijing?

Bought one the last time I was in China while on tour, but the only time I have for shopping this time is in Beijing. Does anyone know where I could purchase them?

You can buy silk duvets in the Pearl Market. I'm not sure where you could buy a silk cover for the duvet. They are sold in measurements as they are not all compatible with our familiar with our terms of "queen size" or "king size" etc.