I bought two Corley Motors shirts from Zazzle during the summer, first one appeared to be quite low quality, but second one was great.
The dark colour ones had a weird white line going around the design and the lighter colour ones look great.
I bet the guy who did those designs to the site got the logos and designs from here.
I have the original shirt also from Lucasarts, found it years and years ago from eBay for 1 dollar, someone didn't really know how rare it is. It's a real shame that the Zazzle colour options didn't have the washed out green colour option that the real one is.