Stir almonds in a 6- to 8-inch frying pan over medium heat until golden, 5 to 6 minutes.
Pour nuts into a food processor or blender. When slightly cooled, whirl to a fine powder.
In a bowl, combine nuts, garlic, mayonnaise, lemon juice, and 1 tablespoon olive oil; mix well.
In a plastic food bag, combine flour, paprika, and salt. Drop in oysters, a few at a time, and shake to coat. Lift from bag, shaking off excess flour mixture. Lay oysters slightly apart on a sheet of waxed paper. Discard extra flour.
Place a nonstick 10- to 12-inch frying pan over high heat. When hot, add 1 1/2 tablespoons oil and swirl to coat pan. Add half of the coated oysters and brown well on each side, turning once, about 2 minutes total. Drain on towels and keep warm.
Add remaining oil to pan and brown remaining oysters.
Serve the oysters with the almond aioli sauce.