Wheels and tires

I have the Gt Bullitt Torq Thruster Wheels and I need to get some new tires. They have the 245/45R17 on them. Will any other size fit? Im seeing them for about 160 a piece for an ok tire. Anyone put a different size tire on them? Also looking an getting a gt hood scoop. Anyone know where to find one cheap?

there are always steals on ebay...