I know the same thing can be made from nickel silver rail and copper-clad sleepers but it's deadly dull to make and probably not that much cheaper. Interestingly (well I found it thus, which probably says something about me) is that the rail itself comes from Sheffield. This is then shipped to the USA, sleepers are attached and then sent back to blighty.
In fact it appears that pretty much all model railway rail comes from Sheffield where it is made by one man. I'd assume that Marcway (based in Sheffield) us him. Kalgarin do for their new range as well. Worryingly, he's approaching retirement age so maybe I should stockpile the stuff ?
Anyway, once the track has come back from the new world, it has a sticker on it. Apparently if you use this stuff in California, the track can cause infertility and birth defects. Presumably you could be born a Great Western modeller. Which would be pretty bad.
Mind you, simply being a railway modeller is likely to harm your chances of reproduction - no matter what you do with the trackwork...