Make the pie crust by incorporating sea salt, flour, and butter until a coarse, sandy-looking meal forms. This can be done in a bowl with your hands or in a food processor. Add cold water and continue working or pulsing the mixture until a dough forms. Shape into a disc (like a hockey puck), wrap in plastic, and chill for at least 30 minutes.
Preheat oven to 350 degrees then start the filling.
Peel and core apples and pears then cut into one-inch pieces. Add fruit pieces to a bowl, followed by dried cranberries, lemon juice, brown sugar, granulated sugar, flour, cinnamon, nutmeg, ginger, clove, and maple syrup. Stir and toss until evenly coated.
Next make the streusel topping. Combine flour, old-fashioned oats, brown sugar, and melted butter until uniform and no pockets remain. The mixture will be thick.
Roll out the chilled pie dough and place over top of a round 8-inch pie pan then press into place.
Fill pan with pie filling and spread it around, as needed, to cover the crust and have a relatively even top.
Spoon streusel topping onto pie filling until covered. Press streusel into pie dough around edges of pan.
Transfer pie to preheated oven and bake for about one hour. Bottom crust should be firm and golden brown. The filling should be thickened, bubbly, and sticky. The streusel topping should be golden brown and firm to the touch.