Leo,
You have a Model 1908 Commercial. The 118,35 is the old method of indicating caliber and represents the number of 9mm round lead balls required to make a pound. It is not particularly rare, but it is uncommon and is a desirable collector item. Hopefully the amount of rust is not extensive. Until you find a gunsmith I would recommend that you keep the gun well oiled to stop the rust and prevent further damage. Rebluing the gun is strongly discouraged as that will destroy most of the collector value. We would very much like to see photos when you can send them.
I believe there are one or two members of this forum that are from Brazil. Perhaps they will notice this thread and be able to assist you. By the way, your English is excellent and far better than my non-existent Portuguese!
Best regards,
Ron