Hello, recounting between my neurones, I think I saw a model of the MSG Ray, you're in luck!, Is here and it's free, I hope you like the design, there are not many by the cloud.
Metal Gear - Chamoo232's Papercraft Archive
Here there is a MGS Rex, down with the mouse and you will find the model,
[[[HILO OFICIAL PAPERCRAFT]]] - Actualización 22/09/10 Dissidia: Final Fantasy | Foro Meristation