Could be the real deal. But "PROP" is probably a very good term to use for this sale.
The rear wheel looks to be sloppily spray painter over to make it look like an older neglected work bike. Who knows if the wheel and chain will even turn unless you strip off a couple pounds of battleship gray flat enamel paint. Not a very attractive memento - even to own just to display among your Godfather curios. But someone would probably buy it for just that. I suspect it is not a complete intact vintage bike.