Mix the cooked sushi rice with rice vinegar and sea salt in a small bowl until well combined.
Slice the sushi-grade salmon and cooked shrimp into long, thin strips.
Peel and slice the avocado and cucumber into thin matchsticks.
Place one sheet of nori on a bamboo rolling mat and spread half of the rice evenly over the bottom two-thirds of the sheet.
Layer half of the salmon, shrimp, avocado, and cucumber across the center of the rice.
Carefully roll the nori from the bottom, using the mat to keep it tight, and seal the edge with a drop of water.
Repeat with the second nori sheet and remaining ingredients, then slice each roll into eight pieces using a sharp, wet knife.
Serve with coconut aminos and wasabi paste for a clean, restaurant-quality meal.