You listing does not include where you live. If you can easily send your camera to the Leitz factory I would strongly consider doing so. First I would email them with a the facts of the matter and the issue of reliability with the camera. It may be particularly helpful if you can scan and attach your previous repair orders and, were I you, a request that they satisfactorily repair this camera without charge. I would not be surprised if they would do so.
I am not familar enough with Leitz practices to speak with any conviction but I know that Zeiss at their homebase has a service counter and will repair items while you wait..I am sure that there must be some items that they cannot repair on the spot. I have read posting by Contax users of having utilized this service.