I only paint these, and make the comic, so I don't know much about how this works - other than any comic shop can get any cover if they order it now.
A: Regular cover by Montynero
B: Variant cover by Simmonds
C: Variant cover by Montynero
D: Variant cover by Dowling
Last time issue 1 sold out in days, and variants were selling for crazy prices.
Contact a comic shop and ask for the comic you want now: http://www.comicshoplocator.com/storelocator