a quick search yielded this from www.oldcrowmodels.co.uk
and this:
this is a main battle tank, and is the most common model, however, the recent complete volumization of the series has a different style tank on the cover:
personally, I prefer the ones on the cover (Volume 3 and 2 cover art pictured above.)
Enjoy... and good luck. I've thought about scratchin' these tanks myself...