Carl,

Thanks for the input.

-The sections in the first NZ link are too shallow - I need a rope "luff" to make the first part of the tramp impermeable with vinyl or something similar.

-The plastic section in the second link is perfect, but plastic might not resist for long.

I checked some of the more important nearby aluminum companies, like www.alcoa.com.br (Brazil is an important producer) but this is hardly a standard section. The only real rigger is www.farol.com.br and the available extrusions are only for masts and very limited in choice.
It'd be necessary to find a naval alloy round or oval section and then cut the groove, but this would destroy the anodization, so painting would be necessary. It is feasible but not practical nor beautifull.

I'd rather buy the proper product in the US. It is easier to pay US dollars and to receive the goods through my brother in Naples (Fl) or via mailbox.

I'm lucky: so far this has been the only part that required asking around. The custom SS parts were easy to make in Rio and the standard deck hardware is excellent - take a look at Nautos (click in "English").

The "to do" list now is:
-Rear seat, tramps, sails, SS stringers and mast/boom/bowsprit/standing rigging - which will come complete from Europe.

Cheers,