I believe that the zeus is extinct.
I have one with a few screws missing and tried to get some replacements. I rang Armotechs number and the phone was answered by BZpaintball and they said they didn't have any.
Well if you want a bit of a project then you can have my G2 cheap.
Basically it needs a new valve screw which got lost somewhere, but I'm not sure what size screw it is. But it comes with all the accessories, hopper adapter, asa bottomline and the long barrel. So if you could find another second hand one you'd have all the spares and accessories you could need.
Otherwise Gunsmoke paintball have some PT Juniors and Delta 68s cheap on their website. http://www.gunsmoke-paintball.co.uk/products.php?cat=165