Try this:
var jsonValueObj = [];
$("#modifiersDiv :checkbox:checked").each(function() {
var v = {};
v.value = $(this).val();
v.price = $(this).attr('data-price');
jsonValueObj.push(v);
});
var jsonValueCol = JSON.stringify(jsonValueObj);'
This should give you an array of Tuples < object, object> at the other end
EDIT:
You could also create a list of a custom class of (Value and Price) and JSON Decrypt to that.