Ducati Mountaineer 90 100 Exhaust Pipe Muffler used

What I believe to be an original exhaust system for the late 100 Mountaineer.  It may be suitable for the earlier 90 models with a change of exhaust nut, not sure.  Perhaps someone can help.

Condition is unrestored and decent, with a nice patina that would be suitable for a runner, not a concours machine.  Includes the rear mount not shown in this listing (central mount shown is some homemade botch job).