If you can't find the toasted sesame seeds, you can make them yourself, putting them on the fire for a few minutes. Toast them over low heat and move them often so as not to burn them.
If you don't have mirin, replace it with an equal amount of sake and a teaspoon of sugar.
The nutrition information shown is an estimate provided by an online nutrition calculator. It should not be considered a substitute for the advice of a professional nutritionist.