Hand Picked Seaweed <---- link
or just google 'hand picked seaweed' and find some other source
Simple Solution = Bringing Hand Picked Seaweed (Nori Sheets) to your favourite Sushi Restaurants & asking them to use those nori sheets for your sushi.
You could even leave a bunch of nori sheets with them at the restaurant for random deliveries.
Letting them know to always use those nori sheets when delivering sushi to your address, and/or letting them know over the phone when ordering.
The below video is ridiculous, as vegan sushi kicks ass, and it doesn't propose the solution that I mentioned above.