I dont know how you could do better than http://mtwilliamsonmotel.com/. They will pick you up at the Onion Valley trailhead, you can spend a night , shower, laundry, repacking your resupply, etc, and be taken back to the trailhead next day. $275 for two people.
OK, you could hitch. But you still need somewhere to stay the night, etc.
Fairly well known JMT blogger Ray Rippel, had a resupply not show up last yr. The packer doing the resupply thought it did, they did not acknowledge any wrongdoing.