For your grocery needs in Shaver Lake visit Ken's Market. Keep in mind, most things in Shaver Lake are more expensive due to the isolation.
42137 Tollhouse Road, Shaver Lake, CA 93664
(559) 841-3549
You might also try Shaver Lake Gas and Food Mart.
41801 Tollhouse Rd, Shaver Lake, CA
(599) 841-2923