I do it every year. Maybe, we don’t have the same kind of walnuts but in my area walnut trees are common enough to go to the woods, find a place with a few trees and fill a 50L bag of nuts in an hour. Do it with two or three people, twice or thrice during the season and the whole extended family have enough walnut for regular consomption until the next automn. When dried properly the walnuts last up to 3 years in their shell. A bit less than 2 years shelled in an airtight box. You do a bunch of in fall and you break the rest progressively during the year, while watching TV.