You can get 18" LM replica's for around $800-900 and 19" for $1,100-1200, depending on width...finding them in a 5x114.3 may be an issue though.

NM, found them for a Lexus. 19x8.5" F and 10" R for $1,300...
http://www.wheeldude.com/catalog/pro...oducts_id=5671



Looks like you can get Ford GT wheels 19x11" rear and 19x8" front for about $1,100...
http://www.wheelsrims.net/ford-gt-inventory.html



Honestly the 18x9.5" Rota P45R might not look too bad, lol!
http://www.wheeldude.com/gallery2/v/newwheels/p45r_001/


or even the 18x9.5" Rota Torque...