They are not very common. Most were natural. Black and white seem to be fairly common. I think the sunburst are the rarest. From the item description it isn't really in collectable condition, but still a great buy at the current bid price.
T-40's with rosewood necks are more rare as well. Sunburst with rosewood is one of the most hard to find. Like this one:
Looks like someone snatched the maroon one already.