So I opted for the plywood. I guess it is some sort of birch but I'm not sure. The thickness is 28 mm, or 1" 1/8. That is way too thick for a saw handle for a child, but removing a layer or two shouldn't be too hard.
Two Guys in a Garage has got a really nice page with loads of scanned handles. I decided that the Kenyon dovetail saw model looked nice.
If I lived in the USA, I would seriously consider buying a folded back and a saw plate from those two guys. Their prices seem more than reasonable,. And from what I can see on their home page, the backs look fabulous. (I am not affiliated with TGiaG in any way etc. etc.)
The only problem with the handle scans are that I can't figure out how to print them in the correct size. I tried various settings, but I still couldn't get it right.. I'm better at woodworking than setting up a printer..
So the handle ended up being 7% smaller than the original, but again since it will be a children's saw, that's just fine. Plus it saves me from the trouble of having to reduce the size.
The plywood is the same that is used for table tops out here, and it is sandwiched between two fat pieces of grain imitating plastic laminate. To mark out the outline of the handle, I taped the print out onto the plywood, and used one leg of a divider as an awl (I haven't got an awl out here). When I had made dots all the way around the handle and also marked the centers for the holes to be drilled, I removed the paper and headed for the pillar drill.
Someone has once purchased a 26 mm drill a bit similar to a Forstner bit. That was perfect for the larger holes on the print out.
The holes for the saw nuts, I only drilled with a 3 mm (1/8") drill, so I can use them later on for exactly marking the saw plate.
One of the large holes was a size of which I didn't have a drill, so I just used the 3 mm drill and made a series of holes next to each other following the curve.
I used a hack saw to saw as close as I felt comfortable to the dots. By doing that I ended up having a coarse shaped fat handle.
The next task will be to reduce the thickness of the handle and refine the shape.
Thanks to TGiaG for provinding scans.
End view of the plywood.