The Crosman Nitro piston should fit in it but not sure what exactly you need to do or change to install one as I've never done one...that's the fairly inexpensive way. Supposedly, Hatsan by the end of the year is going to start selling gas rams...send an e-mail to service@hatsanusa.com to find out if, when and how much.Or you could always also go take a look in the Member Gate as there was another GTA member selling an Edge .22 Vortex for $80 delivered, which considering how much it costs to ship a rifle, is actually a pretty inexpensive alternative and either gives you 2 rifles, which is never a bad thing, or you could sell yours to a friend and offset buying it.Hope this helps a little.