I couldn't help but butt in but those look to me like American Racing Torq Thrust "M"s, hence the M on the center cap. Anthracite. They look 18x10 to me. You can get Running Horse center caps because they are a perfect fit. Torque Thrusts are subtly different than stock (much more beautiful) so its good to have them all around, whether staggered or not. Also, stocks are 17x8, very thin lip.
Kevin