It's definitely Italian-made, and dates from circa the late 1950s through to the 1960s.
My best guess is that it's a Borgani (based in Macerata, Italy), made during the years when they were cranking out student to intermediate grade instruments. These days, Borgani have reduced their rate of production to concentrate instead on making high-end professional-grade horns that are superb, but cost an arm and a leg. I've play-tested a couple of Italian tenors similar to yours. They are solid, worthy players, but not outstanding - which given the market they were aimed at is to be expected. With that said, they're a whole lot better in terms of build-quality and tone-colours than some Chinese-made horns.
More info here, though the left-hand pinky table isn't the same as yours. However, designs were tweaked over the years:-
Selmer London Tenor: Manufacturer Mystery Solved
Assuming that you could track down the neck from any Italian-made tenor sax, it would probably be a good fit "sonically", even if the neck diameter needed to be adjusted to fit.
The only real problem I see is that you'd be investing money in a horn which doesn't have a high intrinsic value. Assuming it already had a neck (and those 2 pearl key-touches weren't missing), then your sax would still only be worth about £200-ish. Heck, this one (looks similar to yours but has a neck and is in better condition) sold on the devil's junkyard a month ago for £10, when you subtract the cost of the £400 overhaul: and the case that's worth £40:-
Tenor sax for £10 (well, sort of!)
I'm not saying don't bother getting a neck for that sax, but just think carefully before you shell out the money. You might want to put the project on the back-burner for a while.