Have you tried Sriraja Panich Sriracha?[1] It's one of the many sauces that claims to be the original Thai version. I liked the taste pretty well, just as much as the version manufactured here although they are different. It doesn't taste anything like Sriracha but I prefer Bachan's BBQ Sauce to Sriracha. [2]
[1] https://www.amazon.com/Sriraja-Panich-Sriracha-Chili-Sauce/d...