I'm looking into this also for a gray interior Accent.
So far, what I have found:
The wheel is about 14.5-inch diameter, but thin.
The Wal-Mart covers that say 14.5-15.5 inch diameter will not fit - about a half-inch gap at the bottom if you mount it tight at the top.
I didn't see anything compatible at AutoZone or Pep Boys or O'Reilly's.
Advance has an Autocraft Line with covers that fit that say "Fits 15-inch or smaller wheels"
There are three that I like, but nothing that is perfect:
AC48204B -
AutoCraft Plain No Logo Black Steering Wheel Cover AC48204B: Advance Auto Parts - This is smooth black (faux) leather. About what I want. Would look great in a black interior. The gray wheel is charcoal and so is the upper dash, but I might go with it anyway.
AC2021G -
Buy AutoCraft SWC, SPORT, GREY AC2021G at Advance Auto Parts - This blends in with the interior better, it is perforated (faux) leather. I like it, except it has little carbon fiber inserts at 2:00, 4:00, 8:00, and 10:00. Not crazy about those and they are right where my hand grips go. I could mount them at 11:00, 1:00, 5:00, 7:00, but I think that would look funny. It it were perforated all around, it would be fine.
AC39731G -
AutoCraft Grey Contour Steering Wheel Cover AC39731G: Advance Auto Parts - this looks better in person, it is charcoal perforated leather, but I'm not crazy about the cutouts - looks like some of the wheel was gauged out.
AC38455G -
AutoCraft Steering Wheel Cover - Grey Stitch AC38455G: Advance Auto Parts - I think this is a bit too light and also looks like an old person's car.
You can also search for small steering wheel covers on E-bay:
small steering wheel cover | eBay
Or for 13.5 steering wheel covers on E-bay:
13.5 steering wheel cover | eBay
This one looks good:
Car Steering Wheel Cover Gray Leather Small | eBay - but it's $25, and I hate buying something like this unseen - it's hard to say what the actual color, feel, texture of it is, etc.