Pink and light green tinged variants of the silver aro seem to getting more and more common. Most of them lose this coloring when they get older but some of them retain it. This might be what your reading about.
some species might develop 'reddish' tinge on their tail or body..but it can't be justified as red variance...it's just like human..some have light skin, some have dark skin..
There were some available here, but they had more and a darker shade of pink on the fins.. They were about 45$ each, pretty expensive compared to the plain silver ones..
The substrate and bacground colors and what the fish eats have great influence on the color"variants". but Silver, Black, Jar, and Lei are it in the USA.