Im not sure about Chicago, but Id bet it has a recycled construction store like the one in Pgh. That one is called construction junction.

You could go for the ikea - Poang, probably their best item. Ive owned one for a while, they hold up well and they look great. ...

you might want to look at ikea or west elm as inbetweens.

I really like the staircase, but just to be fair the idea of right-left staircase is not a new idea.