I should have asked if there is a tree/shrub that produces larger nut meats than the American Hazelnut (Corylus Americana) and hardy in Zone 4b. Thanks.

look into Hazelburt, there may be a few different types. Hardy Fruit Tree Nursery has some.

The nursery you mentioned is sold out of hazelbert. Will look elsewhere, but we have some well growing natives healed in. Maybe big enough if well fertilized. Thanks