Well due to the Power Valve (PV) that is a 87+ cylinder and I know Q makes Q pipes for the 87+ 250 and based on the looks of that being aluminum and o-ringed plus set up for the spring hooks I'd say there is a good chance it is off a 250 Q pipe.

Call Matt Shear he makes the Q pipes for Q he might have or be able to get a hold of another one for this bike.

Or if you just need o-rings you can get the Viton -rings off McMaster Carr