After reading the rave posts, I dragged the Missus out bright and early this morning. In vain. Circle C was nowhere to be found, and the information booth said they're done for the season. Guess I'll have to wait for next year.
Oh no! Sorry you missed them. Last week there was another vendor with mulberries at the Wed FM in Sta Monica--they sell citrus and avocados at the east end of the market. Might be a possibility is you can make it.