Since the 'first version' was made in such small numbers I can well imagine that the earliest 'second versions' had the same spool.
Just how many firsts are out there? About 50 I think.
Carpano et Pons didn't compile any production records until 1948 and the changes they made, as production continued, were numerous, but I am confident they didn't halt production to bring in a new modification, but rather brought them in as spares were used up on the production line.
For this reason the 'version' thing can cause confusion. If one is listing a number of changes and saying this is the next version, one is probably incorrect. The changes would have been gradual and there might be slightly different reels coming off adjacent production lines for several days.

- mitchell factory building station.JPG (58.84 KiB) Viewed 85657 times
Here's one of the assembly lines. You can see various parts all jumbled up together, but it looks as though the lid is lifted and the parts allowed to tumble down to the tray below. I can well imagine new parts getting to the bottom before old ones are all used.
The eagle-eyed will spot that the shims are large diameter, but the paint on the spares boxes is the real clue here. It is Finnegans Hammerite which was sold to manufacturers all over the world from their Northumberland factory. It was available by mail order in the UK so the public could buy it, but only in a brushable form, not thinned for spraying, and the special thinner was not available to the public.
So I'm pretty confident this image is from the very late Sixties or very early Seventies which seems to be the only period that Hammerite was available to munufactureres..