Try Goodwill or Salvation Army, and the patterns don't need to match, not in the camper! I picked up a handful of Corelle saucers last winter, the stack probably cost me under $5, but I use them for everything. When it's just me, even when I'm cooking, lots of times a saucer or a custard cup is all I need to hold ingredients, or to heat up a snack. I found several salad or lunch-sized plates in a pattern of stoneware I like, but wouldn't it turn out they're fairly scarce. I have a tan colored set of 5, here are six in a nice green color. I may only ever have just the five. :)

An eBay item sold and was paid for this afternoon, so I ship the box tomorrow. The Tupperware tub that wasn't doing anything useful here will go to a new home.