If you are looking for a reliable highly professional person to carry out servicing and repair then please check out Curta Italia. Romano offers a personalised service at very reasonable rates considering the the quality of work and time spent.
I sent an early type two which must have been seized for 50 years, communication was excellent and a fixed price was agreed prior to any work being carried out (if your not happy with the quote there is no obligation). When I received the Curta back (about 10 working days) it was well packaged and in faultless working condition.
I was nervous about sending one of my most prized possessions to Italy to someone unknown to me but I need not have worried. Romano sent regular updates in perfect English and kept me informed through the process, I would recommend him without question.

Review/recommendation much appreciated, cheers.