due ruote 

That's cool, but I think maybe that's a C-Record (?) post and what I have is a Victory. The post has a cavity where the bolt head goes so it's not visible from that view.
As luck would have it, I went to the hardware and used their thread board to determine that it is in fact a M8 x 1.0 x 35mm bolt that I need. And although they only stocked coarse thread, I was able to find one on Ebay for $7. Cool, right? Almost. Only then did I realize that I had found all the bits except the contoured thrust washer (or whatever it's called) that goes under the bolt head. I returned to the scene of the crime and did a few slow passes, but no luck finding it.
So now I am looking at this seatpost and thinking OK, I will never find one of these bits, but really how hard could it be to fab. one?
Does anyone have a Victory post laying around? I would love to see a picture of the wedge piece and get a couple measurements. I tried Velobase but keep getting security warnings, so I haven't actually seen what's there.