I searched until I found a sink just big enough for a plate to sit in. I am not sure of the brand or model right now as I did this in early 2017. I found one in SS we both liked. We prefer it to be a reasonable size for a couple of reasons. One is not wasting a lot of hot water filling a large sink. The other is to minimize the over filling of our grey water tank which is the biggest issue with tank sizes.
Regardless, installing a sink that fits well (and this is another size concern) is quite easy. I have installed many hundreds of sinks before though.
All this said, I much prefer to do the dishes in a plastic bin outside where I can watch nature do its thing, the main reason we go camping in the first place.