Second: the Chinese market nowadays is too important for ETA/the Swatch Group to not have Chinese date wheels in their movements. Again - for the 1970s the story is different - at that time China was no market at all.
Third: there are 2836-clones with and without 'Swiss Made' on the movement. To the trained eye the difference between a clone and the original is mostly obvious, to the layman it is not. So without detailed movement shots nobody here will be able to tell you the differences.
Fourth - a watchmaker incapable to replace a standard date wheel on a standard movement is not really worth his salt. My opinion.
Last point: does the watch run satisfactorily? If it doesn't, return it for an improvement on the repair job. At almost 400 $ you can expect them to do a decent job.
Sent from my iPhone using Tapatalk