Looks like the remains of a 160 Monza Jr. (The cam cover on the other side should have "160" on it) I'd have a hard time paying more than $100 for it. I bought a complete one last year for $200. Hard to tell much by those pictures, but judging by what I can see of the battery tray I'm guessing it's a '66, '65 at the earliest.
As Ducati's go, it isn't all that desirable. The 160s are still neat, but most people want the 250 or larger bikes. The 160 engine doesn't share many (any?) parts wth the larger bikes, the frame is different, the wheels smaller, suspension is cheaper, etc.
That said, they still have their fans... like me. ;-)
Here are a couple shots of my current 160 project.
As received:
Current condition:
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