[Electro]

The spring perch does look pretty close to the stock wheels as it is, I would be a bit worried about going bigger. But nonetheless, here's a video of wheel and tire specs.

Tapered Lug nut - 3/4"
5x105
17x6.5 +44

Tires weight 21lbs
Rims weight ~24lbs

 

[EldRick]

Actually, there are a number of inexpensive performance wheels available in the 17-18 lb. range, in 7.5" width or wider.
These have the correct bolt-pattern and offset, but the hub diameter will be larger than 56.6, so you will be lug-centric, rather than hub-centric. Also, they will typically have two sets of bolt holes, and will fit both 5x105mm and 5x110mm patterns.
Try Discount Tire or even eBay, rather than the Tire Rack - you'll find a number of choices.