The image looks like bent steel to me.
Usually when I call out something this funky, I would have already seen if this was possible and referenced a company with the capability. I get clients who's in-house designers, design this type of thing. If this was sent out to bid, I can almost guarantee everyone is scrambling to see if this is possible.
This place near you says it can cut material within a 1 degree taper... thats well within allowable tolerances for your text, but doing it in steel seems problematic to me. I would call these guys.
http://www.watercutinc.com/waterjet-cutting.asp