I learned in an NLP training course that the best way to learn foreign language pron is through modeling.
So I think either of the modeling based paraliminals (NBG IPM) would help.
Also you might want to try belief ("I believe I speak xxx like a native") that might help too.
Also, you might try anxiety free. I've studied a few languages, and I've found (both personally as a learner and as a foreign language teacher) that anxiety is a big road block to speaking with the correct accent. People are worried about sounding stupid when they speak.
Anyways, good luck!
George