I can't be 100% sure without seeing it, but the 2 spoke one on eBay looked to have some issues:

The countersunks in the wheel don't line up with the bolt heads in places.
The Munari signature is not stamped into the metal, 'looked more like engraved.
I didn't like the way the horn button was illustrated but not included, even though it was stated as such.
Otherwise, the steering wheel had nice original patina on the leather parts. It was a proper Ferrero, no doubt.
I'm pretty sure Fulvia bosses have the same splines as X1/9, but probably not the same horn contact?