Diane, I have some 215/50-13 Kumhos you can look at, they're about 21.5" tall compared to 23" for a 205/50-15 tire. This is probably the cheapest tire you can get into that is short enough to make it worthwhile. Hoosier has the 225/45's and 225/50's, and Yoko does a 215/50-13 as well, but they're all $40-60 per tire more expensive.

Bob