recoil system for WE katana raptor?

[Christopher_2000]

Dose anyone know if you can you buy a recoil system for a WE Katana Raptor.

 

[ak2m4]

They're split gearbox right? Only aftermarket product I can think of is the Tremors kit by Modify - I fitted one about 6 years ago, real pain in the arse. Too much trouble for what is it. However I don't think it would fit on a Katana and the piston is closed.