There are quite a few named Alley marbles but I do not think this is one of them. The type is commonly referred to as a swirl. Alley is one of the several West Virginia companies that made them. And many of those companies produced very similar marbles - sometimes it is very difficult to attribute a particular marble to a particular company, in which case, they are commonly referred to as "West Virginia Swirls".
I think yours is an Alley Swirl.