How much was a Mars bar in 1960?

then that depends on the size of a standard sized single bar is about 89 cents depending on where you live and if food it taxed.

in a 62.5 gram mars bar there are 11 teaspoons of sugar.

Depends on which one. usually around $2.50

43.6 grams or 11 teaspoons of sugar. Source: createyourself.co.uk/item/85