Trust me, you don't want to. I have seen many brands of bottled pad thai sauce on store shelves, and I have never come across one that comes close to the authentic flavour of real pad thai. Most of these sauces are overly sweet, and use cheap ingredients that compromise the flavour. For example, instead of palm sugar they use granulated white sugar. Instead of fish sauce they add salt and maybe even soy sauce which is not the right flavour. And instead of using all tamarind they will mix in white vinegar or rice vinegar which is much cheaper. They also often add a lot of additives and colour that are totally not necessary. Pad thai sauce uses only a few ingredients, and the store that sells the bottled sauce probably also sells all the ingredients you need to make a much better one yourself!