Slice the Spam into about 8-10 slices depending on how thick you like it. Place it in a Ziplock bag.
Mix oyster sauce, soy sauce, and sugar until sugar is dissolved and add to the bag with the Spam. Marinate for 15 minutes.
Drain off marinade and fry Spam on each side over medium heat until slightly crispy or until desired doneness.
Place a strip of nori roasted seaweed on a cutting board (shiny side down). Place your Musubi mold across the middle of the nori.
Add Sushi Rice to the mold, pressing down firmly and evenly so there is about 1-1 ½ inches of rice. Dip the mold and your fingers in water as you go to prevent sticking.
Optional: Add a sprinkling of furikake for extra flavor.
Remove the mold from the rice. Now you will have a nice little block of rice right on the nori. Add a slice of cooked Spam on top of the rice.
Wrap up one side of the nori and stick it to the top of the Spam, then wrap up the other side. Use a little water on your finger to seal if needed.
Serve warm.
