Getting Sakurab for the Palapa when you are living outside the Philippines is difficult, but you can use the white part of the spring onions to replace the Sakurab. The taste won't be exactly the same, but it is close.
To make the substitute, simply place about 1/2 cup of white part of spring onions, chilis (depending on the level of spiciness you want), and about 1/2 tbsp of chopped ginger in a small food processor or just pound it by using mortar and pestle. Then, this is ready to be used.
Bear in mind that, sometimes, it comes about bitter when eaten raw because of the ginger. Just don't overdo the ginger.