The reason they want the old trucks is simple...even an economist can figure it out...most of the tracks are dual gauge....
As for it being simple to built a gondola, and any clod with a sheet metal brake and some welding rod can do so..I am pretty sure the folks at Johnstown and Trinity Railcar would argue that some...
It isnt simple, it takes a huge amount of capital investment, and you have to make a lot of the same car over and over to make any money at it.
What the railroads in Brazil are buying are small lots of new speciality cars, in the 50 cars or less range.
Thats not to say the hoppers mentioned here are on the way to Brazil...but it is quite possible they are.
Until recently, the railroads there were nationalized, and ignored.
It was cut up and sold off to several operators, and they are buying locomotives and rolling stock to fit specific needs of their lines.
As for Brazil being a heavy industry country...not really, but thats a different argument.
They have one manufacturer that cast trucks...one.
This company make narrow gauge trucks for rolling stock, and the narrow guage trucks under the locomotives.
Your an economist...so why dont we, America, with all of our industrial might and know how, why dont we make Cooper Minis here?
Because quite simply, the market dosnt exsist to justify the investment in the plant.
But oddly enough, the market does justify the making of other things, like racing brake rotors and racing intakes manifolds for the Minis...but only by small, Mom and Pop speciality companies.
No one in Brazil is going to invest the money in a railcar maker, until the market there grows to the point it can support such a venture...no matter how cheap the labor.
So, yes, it is cheaper to buy the "simple steel boxes" somewhere else, and pay the shipping cost...
Before you wonder...and run off a little more SWAG...my information comes from a member of Brazil's Army, he is part of the office that handles military movements via rail, he has been an American railroad fan since he was a kid, and is tickled to death to see all the SDs and C-30s showing up, his other job is with the logistics company that coordinates the shipping of a lot of this stuff.
He and I had this exact same conversation a few years ago, I too wondered why they were buying all this crap, and the odd batch of new stuff, and I too, asked him why they didn't just build it themselves...