It's possible to widen steel wheels by welding in a metal sheet but, I am not sure if it's even possible to widen alloy wheels. If it is, than probably the labor will cost you a good amount of $.
As an alternative you can take a look at aftermarket 17x9 rims, or even get a staggered setup for very cheap. There are hundreds of affordable wheel brands that wouldn't cost you much, just take a look
here for example.