I always see it at either 99 Ranch Markets or the Hang Kook Korean Market chain. Don't know about W.L.A. but, there's one on the corner of Reseda and Devonshire. (May not be Hang Kook any longer)
I've never seen it at the farmers market (though that doesn't mean it hasn't been there). I think I've purchased it from Samosa House - try giving them a call.
----- Samosa House 11510 Washington Blvd, Culver City, CA