What's a "Forist"? Do you mean Forumists? We usually just say members.

Welcome to the board. There are several other South Americans here, including at least one Argentine.

Some specialist will probably be along to answer your question fully. But you may wish to think of the overall size of the gun if you want that short a barrel, and of the advantages of stainless steel in maintenance. I'd suggest a Model 66, unless you plan to fire many .357 Magnum loads. The M-686 is a rather large gun to easily conceal.

Which handguns are widely sold there? I've seen some made at the arsenal in Rosario. We have those here, and some Bersa products.

I'm glad to know that you can buy a .357 Magnum. Brazilians seem unable to buy more than a .38 Special.

Good luck on getting the gun that you decide that you want.