Ebay should have some, but they will likely be more expensive. I know someone on here has the older style black Pontiac center caps on their 09 model, so that is also a consideration. I find those at the pick a part quite often and have an extra set somewhere.
Thomas
the "Mustang Guy"
1987 5.0 LX Mustang
2016 Mustang GT - current daily
2004 Satellite Vibe &
2009 Red Vibe GT -twin's cars
2003 Neptune Vibe GT - prior daily
2010 Red Vibe GT - RIP 6/16/14
2006 Platinum Vibe - son's car
If you do not have a lead at a local parts yard, would 2nd trying ebay. If the finish is an issue, take the replacement and your Vibe's center caps, wet sand them with 2000 grit or finer then re-clearcoat them. The factory finish seems to dull, as long as the replacement is not gouged, minimal effort will get you a matched set.