We will travel from Naples to Sorrento and one option is to take Circumvesuviana to Pompeii, store our luggage, tour Pompeii and Mount Vesuvius, and then continue to Sorrento via Circumvesuviana. We will have 2 traveling backpacks for storage (not day backpacks). Are luggage storage lockers readily available at the Pompeii station, and if so, what is the cost? We could store the luggage at the Pompeii entrance, but then we would have to go back to retrieve them after our visit to Mount Vesuvius.
Lower level of Station; €8 per day, i believe.
The Pompeii Porta Marina entrance luggage check is only two hundred, level, feet from the Pompeii Scavi-Villia Mistiri Circumvesuviana station. We didn't bother with Vesuvius.
You understand that the train to Pompeii Scavi [where there is a baggage drop] departs from Garibaldi, downstairs at Napoli Centrale.
https://www.sorrentoinsider.com/en/naples-to-sorrento-train-schedule
The luggage check at the Porta Marina entrance to Pompeii is free and only a 1-2 minute walk from the Circumvesuviana station. I assume you were thinking it was a much longer walk.