im sitting here playing around with the modification rules in arsenal, and start to think that the stuff i create could be sold pre-made in game if one account for the cost of work hours needed to do all the modifications.
hell, i discovered that the book holds a tracked modification, and the heavy turret is allowed on any vehicle with a body of 14 or greater. so while there are no straight tanks in the book, modifying an existing one into a tank isnt exactly hard (kinda like how i turned catepiller vehicles into tanks using rigger3 after they errataed the heavy turret requirements).