ROSSI and NOVA ROSSI, they are two different entities.
The pipe to use is the ROSSI pipe for the 12. Trinity is the agent for ROSSI, contact them, ask for the maching pipe. It's possible that they have not brought the thing in to the US. If you intend running a ROSSI R12 PIXI then I would suggest you ask for this pipe.
Dave, tell 'em.