Silver Lake is awesome and has a state park with very few amenities or a private park for RV's and has cabins and a restaurant. It is really close to Lee Vining and the Tioga Pass entrance to Yosemite Park. You could go up the pass and do a day stay at Yosemite and come back down to Silver Lake it is located on the June lake loop. Here is a link to the private RV and cabin campground.
http://silverlakeresort.net/