You may get an SLP who does nothing for you, unfortunately. All too common. One who has worked with multiple languages would obviously be ideal. STS is tricky to look up, but it's fairly simple in concept. Basically you match your speech to a metronome beat. Speak a syllable per beat. You start at the slowest you need to...perhaps 60 bpm or slower. You gradually, gradually increase the speed over a period of time (months?) as long as you remain fluent. Practice 2-3 times per day for five-ten minutes. That's the basic principle. Ideally, this provides your articulators ample time to establish the proper motor programming to say those harder stops. You might try it and see how it works. I bet you could find a metronome app in about 30 seconds.